Leptin secreted by adipocytes promotes EMT transition and endometrial cancer progression via the JAK2/STAT3 signalling pathway

BACKGROUND

Endometrial cancer is a malignant tumour with a high incidence and mortality rate, and obesity is one of the most significant risk factors for the disease. However, it remains unclear whether leptin affects cell activity, proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT).

MATERIALS AND METHODS

Samples of endometrial cancer tissue were obtained from clinical patients and nude mice Enzyme-linked immunosorbent assays (ELISAs) were performed to assess leptin levels. Western blotting, immunohistochemical (IHC) and immunofluorescence (IF) analyses were conducted to detect EMT, JAK2/STAT3 signalling pathway proteins, and cell proliferation biomarkers. Cell Counting Kit-8 (CCK-8) assays, 5-ethynyl-2'-deoxyuridine (EdU) staining, and Transwell assays were used to evaluate cell activity, proliferation, migration, and invasion, respectively.

RESULTS

ELISA, western blot and immunohistochemistry (IHC) analyses showed that leptin was highly expressed, and the JAK2/STAT3 signalling pathway was activated in endometrial cancer patients. Cell-based experiments showed that adipocytes secreted leptin, which increased the levels of leptin, and also promoted cell migration and invasion, EMT transition, and cell activity and proliferation. Leptin accelerated cell progression and promoted EMT via the JAK2/STAT3 signalling pathway in a dose-dependent manner. The tumour-promoting effect of leptin on endometrial cancer cells was further verified by in vivo experiments, in which leptin promoted tumour growth and activated the JAK2/STAT3 signalling pathway.

CONCLUSION

Leptin secreted by adipocytes promotes EMT transition and endometrial cancer progression via the JAK2/STAT3 signalling pathway in a dose-dependent manner.Highlights Endometrial cancer patients have high levels of leptinLeptin promotes EMT transition via the JAK2/STAT3 signalling pathwayLeptin promotes endometrial cancer progression via the JAK2/STAT3 signalling pathwayLeptin promotes endometrial cancer in a dose-dependent manner.

Adipokines in depressed women with and without adverse childhood experiences

BACKGROUND

Adverse childhood experiences (ACE) elevate the risk of both major depressive disorder (MDD) and metabolic diseases. The underlying pathophysiology might include alterations of adipokine levels as a consequence of ACE. In this study, we used a full-factorial design to investigate the levels of select adipokines in women with ACE-only (n = 23), MDD-only (n = 27), ACE+MDD (n = 25) and healthy controls (HC, n = 29) to identify metabolic makers associated with vulnerability and resilience of developing MDD after ACE exposure.

METHODS

Serum levels of adiponectin, leptin, adiponectin-to-leptin (A/L) ratio, and retinol binding protein 4 (RBP4) were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Adiponectin levels did not differ between groups. Individuals with vs. without MDD showed higher leptin serum concentrations. As predicted, A/L ratio indicated lower values in individuals with vs. without ACE. RBP4 showed a more nuanced pattern with reduced levels in the ACE-only and MDD-only groups compared to HC. Furthermore, the ACE-only group showed lower RBP4 concentrations compared to ACE+MDD. These results were not accounted by BMI or medication status.

CONCLUSION

Our results do not support the utility of adiponectin and leptin as predictors of vulnerability or resilience of developing MDD after ACE. In contrast, RBP4 might play a role in resilience towards the development of MDD following ACE. Further research on this more recently discovered adipokine seems warranted.

Association between Toxoplasma gondii and gestational diabetes with regard to serum leptin and tumor necrosis factor alpha, a preliminary study

Gestational diabetes (GDM), the onset of any degree of glucose intolerance during pregnancy, increases a wide range of adverse health outcomes for both the mother and the fetus. The aim of the present study was to evaluate the association of Toxoplasma gondii infection with GDM in a case-control study with regard to the levels of leptin and tumor necrosis factor alpha (TNF-α) as two inflammatory biomarkers. Fifty-one pregnant diabetic cases and 109 controls were selected from a prenatal care clinic of a general hospital in Shiraz, southern Iran during July-November 2020. Cases and controls were similar in age, gestational age and number of parturitions. The presence of IgG antibodies against T. gondii, and serum concentrations of leptin and TNF-α were determined by ELISA. Anti-Toxoplasma antibodies were detected in 25 subjects (15.6 %, 95 % CI: 9.9-21.3). Nine (18 %) diabetic cases were infected with Toxoplasma compared to 16 (15 %) healthy controls (P = 0.63). Level of leptin was higher (P = 0.07) while TNF-α was lower in diabetic cases compared to healthy controls (P = 0.08). When subjects were classified according to the combination of GDM and T. gondii, leptin was significantly lower in healthy (non-diabetic, non-infected) subjects compared to diabetics (P = 0.026), and TNF-α was higher in healthy subjects compared to Toxoplasma-infected diabetics (P = 0.032). These findings can be interpreted as both comorbidities being individually associated with increasing serum leptin and decreasing TNF-α concentrations, with modifying effects on each other. The present study opens a new perspective on GDM and its complex pathophysiological mechanism. Future research in this area is needed to better understand the underlying pathway for the development of GDM and the role of T. gondii and inflammatory biomarkers.

Characterization of circulating leptin-receptor levels following acute sleep restriction: A pilot study on healthy adult females

BACKGROUND

Insufficient sleep adversely affects energy homeostasis by decreasing leptin levels. The underlying physiological mechanisms; however, remain unclear. Circulating leptin is well described to be regulated by its soluble receptor (sOB-R). Intriguingly, the impact of short sleep duration on sOB-R levels has never been characterized.

AIM

In this study, we investigated, for the first time, the variation of sOB-R levels and its temporal relationship with circulating leptin upon acute sleep restriction.

METHODS

Five adult females were maintained on an 8-hour sleep schedule (bedtime at 00:00) for 1 week before restricting their sleep to 4.5 h (bedtime at 03:30) on 2 consecutive nights. Balanced meals were scheduled to specific hours and sleep was objectively measured. Four-hour blood samples were regularly collected during waking hours between 08:00 and 00:00.

RESULTS

Sleep restriction resulted in lower leptin (20.9 ± 1.7 vs 25.7 ± 1.7 ng/ml) and higher sOB-R concentrations (24.4 ± 1.2 vs 19.8 ± 1.6 ng/ml). Neither the discordant temporal relationship nor the pattern of leptin and sOB-R were altered in response to sleep restriction.

CONCLUSION

Our results suggest that sleep restriction may modulate circulating leptin levels and possibly metabolism via upregulating its soluble receptor. This observation may have valuable therapeutic implications when considering sOB-R as a potential target during the management of metabolic disturbances.

Novel mechanisms involved in leptin sensitization in obesity

Leptin is a hormone that is secreted by adipocytes in proportion to adipose tissue size, and that informs the brain about the energy status of the body. Leptin acts through its receptor LepRb, expressed mainly in the hypothalamus, and induces a negative energy balance by potent inhibition of feeding and activation of energy expenditure. These actions have led to huge expectations for the development of therapeutic targets for metabolic complications based on leptin-derived compounds. However, the majority of patients with obesity presents elevated leptin production, suggesting that in this setting leptin is ineffective in the regulation of energy balance. This resistance to the action of leptin in obesity has led to the development of "leptin sensitizers," which have been tested in preclinical studies. Much research has focused on generating combined treatments that act on multiple levels of the gastrointestinal-brain axis. The gastrointestinal-brain axis secretes a variety of different anorexigenic signals, such as uroguanylin, glucagon-like peptide-1, amylin, or cholecystokinin, which can alleviate the resistance to leptin action. Moreover, alternative mechanism such as pharmacokinetics, proteostasis, the role of specific kinases, chaperones, ER stress and neonatal feeding modifications are also implicated in leptin resistance. This review will cover the current knowledge regarding the interaction of leptin with different endocrine factors from the gastrointestinal-brain axis and other novel mechanisms that improve leptin sensitivity in obesity.

Leptin moderates the relationship between sleep quality and memory function: A population-based study

Sleep is crucial for memory, as it promotes its encoding, consolidation, storage, and retrieval. Sleep periods following learning enhance memory consolidation. Leptin, a hormone that regulates appetite and energy balance, also influences memory and neuroplasticity. It plays a neurotrophic role in the hippocampus, enhancing synaptic function and promoting memory processes. Given these associations between sleep, memory, and leptin, this study aimed to evaluate the interplay between sleep quality, memory complaints and leptin levels. Using data from the São Paulo Epidemiologic Sleep Study (EPISONO) 2007 edition, we analyzed data from 881 participants who underwent evaluations for subjective sleep quality (Pittsburgh Sleep Quality Index), memory function (Prospective and Retrospective Memory Questionnaire), body mass index and plasmatic leptin levels. After confirming that subjects with poor sleep quality had more memory complaints in our cohort, we observed that leptin levels were increased in individuals with more memory complaints, but there was no association between leptin levels and sleep quality. Mediation analysis reinforced the direct effect of sleep quality on memory function, but leptin had no indirect effect as mediator over the sleep-memory association. Moderation analysis revealed that leptin acted as a moderator in the relationship between sleep quality and memory, with increased leptin levels enhancing the effect of sleep quality over memory function. These findings underscore the intricate interplay between sleep, memory, and metabolic factors like leptin, shedding light on potential mechanisms through which sleep influences memory and cognitive functions. Further research is needed to elucidate the exact mechanisms underlying these relationships and their implications for overall health and well-being.

Leptin receptor reactivation restores brain function in early-life Lepr-deficient mice

Obesity is a chronic disease caused by excessive fat accumulation that impacts the body and brain health. Insufficient leptin or leptin receptor (LepR) are involved in the disease pathogenesis. Leptin is involved with several neurological processes, and it has critical developmental roles. We have previously demonstrated that leptin deficiency in early life leads to permanent developmental problems, including energy homeostasis imbalance, melanocortin and reproductive system alterations and brain mass reduction in young adult mice. Since in humans, obesity has been associated with brain atrophy and cognitive impairment, it is important to determine the long-term consequences of early life leptin deficiency in brain structure and memory function. Here, we demonstrate that leptin-deficient mice (LepOb) exhibit altered brain volume, decreased neurogenesis and memory impairment. Similar effects were observed in animals that do not express the LepR (LepRNull). Interestingly, restoring the expression of LepR in 10-week-old mice reverses brain atrophy, as well as neurogenesis and memory impairments in older animals. Our findings indicate that leptin deficiency impairs brain development and memory, which are reversible by restoring leptin signaling in adulthood.

The 40-min HIIT acutely induced bone formation which was likely through the increases in muscle derived interleukin 6 and adiponectin activation: The 16 weeks of HIIT intervention, longitudinal randomized controlled trial

PURPOSE

There is some controversy regarding cytokines released from adipocytes, particularly adiponectin, leptin, and IL6 that regulate bone remodeling. In addition, IL6 is released from muscle contraction, which might have a distinct role in bone remodeling. Hence, this study investigated whether muscle contraction during a session of 40 min of high intensity interval training (40-min HIIT) and after 16 weeks of HIIT (16-wk HIIT) altered the release of those cytokines and bone remodeling in overweight women.

METHODS

In total, 22 overweight, premenopausal women were randomly assigned to either the exercise or the control group. The exercise participants engaged in the 40-min HIIT session at 80-90 % of their heart rate reserve (HRR) three times weekly for 16 weeks, while the control participants performed their routine daily activities. Blood was drawn after overnight fasting and immediately after completing the 40-min HIIT sessions to investigate the association of adiponectin, leptin, IL6, CTX, and P1NP through the acute effect of the 40-min HIIT sessions. This process was repeated after the 16-wk intervention program to observe the training effect of HIIT on cytokines linkage. The bone mineral density (BMD) levels of the distal tibia, femur, and lumbar spine were determined prior to and after the 16-wk intervention using dual-energy X-ray absorptiometry.

RESULTS

The P1NP level increased by 8.29-20.52 % (95 % CI) and by 2.91-15.54 % after completing the first and last bouts of the 40-min HIIT sessions, respectively. In addition, IL6 increased by 13.39-28.03 % (95 % CI), while serum CTX and adiponectin were unaltered from the acute effect of the 40-min HIIT sessions. There was an association between the increases in P1NP and adiponectin (r = 0.682, p = 0.015); however, the increase in P1NP was mostly associated with the increase in IL6 (r = 0.572, p = 0.054) after completing a 40-min HIIT session. After the 16-wk HIIT program, the resting adiponectin level of the exercise participants increased; however, this was associated with neither bone biomarkers nor BMD. The BMDs of the exercise participants were maintained; however, the tibial BMD of the control participants decreased with an increase in the resting CTX level after 16 weeks.

CONCLUSION

Muscle contraction during the 40-min HIIT session elevated the IL6 level, which might have subsequently enhanced bone formation. Furthermore, the association between acute changes in adiponectin and P1NP suggested the possibility of an increase in the sensitivity of the adiponectin receptor in osteoblasts.

Serum levels of sirtuins, leptin and adiponectin in women with pregnancy-induced hypertension

INTRODUCTION

Pregnancy-induced hypertension (PIH) and preeclampsia (PE) are associated with disturbed maternal inflammatory response, oxidative stress and vascular endothelial cell dysfunction. Obesity is one of risk factors of PE. Leptin is elevated in obesity and its level correlates positively with the amount of adipose tissue. In contrast, adiponectin levels are decreased in obesity. Sirtuins are expressed in the placenta, however their role in pregnancy-related pathology in humans is not known.

AIM OF THE STUDY

The aim of our study was to measure serum concentrations of selected sirtuins, adiponectin and leptin in healthy pregnancy and in women with PIH.

MATERIALS AND METHODS

The study included 70 women: 38 healthy pregnant women and 32 women with PIH. Blood samples were obtained between the 20th and 40th week of gestation. Serum levels of sirtuins 1, 3, 6, leptin and adiponectin were measured with ELISA.

RESULTS

Leptin levels were significantly higher in PIH group as compared to the controls and correlated positively with BMI. Highest leptin levels were observed in women who needed a cesarean section. Levels of sirtuins 1, 3 and 6 were similar in both groups and did not correlate with BMI.

CONCLUSIONS

High leptin levels in PIH women during 3rd trimester might be helpful to predict the necessity for a caesarian section. Blood levels of sirtuins 1, 3 and 6 measured after the 20th week of gestation cannot be regarded as a single diagnostic test for PIH or preeclampsia. More studies to clarify significance of sirtuins in PIH and PE development and diagnosis are needed.

Peripheral biomarkers as a predictor of poor prognosis in severe cases of COVID-19

We evaluated glycemia and triglyceride, hepatic, muscular, and renal damage markers, redox profile, and leptin and ghrelin hormone levels of COVID-19 patients. We also realized statistical analysis to verify the potential of biomarkers to predict poor prognosis and the correlation between them in severe cases. We assessed glycemia and the levels of triglycerides, hepatic, muscular, and renal markers in automatized biochemical analyzer. The leptin and ghrelin hormones were assessed by the ELISA assay. Severe cases presented high glycemia and triglyceride levels. Hepatic, muscular, and renal biomarkers were altered in severe patients. An oxidative stress status was found in severe COVID-19 patients. Severe cases also had increased levels of leptin. The ROC curves indicated many biomarkers as poor prognosis predictors in severe cases. The Spearman analysis showed that biomarkers correlate between themselves. Patients with COVID-19 showed significant dysregulation in the levels of several peripheral biomarkers. We bring to light that a robust panel of peripheral biomarkers and hormones predict poor prognosis in severe cases of COVID-19, as well as correlates between them. Early monitoring of these biomarkers may conduct the correct clinical intervention associated with the clinical symptoms for treating patients infected by SARS-CoV-2.

Leptin's Inverse Association with Brain Morphology and Depressive Symptoms - A Discovery and Confirmatory Study Across Two Independent Samples

BACKGROUND

Major Depressive Disorder (MDD) has a complex, bi-directional relationship with metabolic dysfunction, yet the neural correlates of this association are not well understood.

METHOD

In this cross-sectional investigation, we employed a two-step 'discovery and confirmatory' strategy, utilizing two independent samples (Sample 1: 288 participants, Sample 2: 196 participants) to examine the association between circulating indicators of metabolic health (leptin and adiponectin) and brain structures in individuals with MDD.

RESULTS

We found a replicable inverse correlation between leptin levels and cortical surface area within essential brain areas responsible for emotion regulation, such as the left posterior cingulate cortex, right pars orbitalis, right superior temporal gyrus, and right insula (standardized beta coefficient (SBC) ranged: -0.27 to -0.49, puncorrected <0.05). Notably, this relationship was independent of C-Reactive Protein levels. We also identified a significant interaction effect of leptin levels and diagnosis on the cortical surface area of the right superior temporal gyrus (SBC = 0.26 in sample 1, SBC = 0.30 in sample 2, puncorrected < 0.05). We also observed a positive correlation between leptin levels and atypical depressive symptoms in both MDD groups (r = 0.14 in sample 1, r = 0.29 in sample 2, puncorrected < 0.05).

CONCLUSION

The inverse association between leptin and cortical surface area in brain regions that are important for emotion processing and leptin's association with sleep disturbances supports the hypothesis that metabolic processes may be related to emotion regulation. However, the molecular mechanisms through which leptin might exert these effects should be explored further.

The effect of leptin gene polymorphisms (LEP rs7799039 and LEPR rs1137101) on febrile neutropenia

Background and aim

Leptin is mainly produced in adipose tissue and released into systemic circulation. Leptin and its receptor LEPR activate the Janus kinase/signal transducers and activators of transcription signaling cascade and increase cytokine discharge. In our study, we aimed to examine the role of leptin gene (LEP) rs7799039 and LEPR rs1137101 polymorphisms on the susceptibility for febrile neutropenia (FEN) attacks and their relationship with clinical findings during the course of FEN.

Methods

This study included pediatric patients with a diagnosis of malignancy who applied to the pediatric emergency department between December 2019 and June 2022 and healthy controls. The genotypes of the LEP rs7799039 and LEPR rs1137101 genes were statistically compared between patients and healthy controls. In addition, the relationship between the genotype distribution of LEP rs7799039 and LEPR rs1137101 polymorphisms and clinical features during the course of FEN was investigated.

Results

In the statistical analysis in terms of LEP rs7799039 and LEPR rs1137101 genotype distributions between the patient and healthy groups, there was no significant difference. Patients with the AA genotype of LEPR rs1137101 polymorphism had significantly more commonly a body mass index (BMI) value of <25, and all the patients with the AG/GG genotype had a BMI value of 25 and above. LEP rs7799039 and LEPR rs1137101 genotype distributions were not statistically significant with other clinical features.

Conclusions

It was revealed that leptin gene polymorphisms did not have a significant effect during the course of FEN.

Study of association of leptin with leukocyte telomere length in a Chinese rural population

BACKGROUND

Previous studies have demonstrated the relationship between adipocyte factors, insulin resistance, and other indicators with telomere length. However, these studies did not consider the influence of changes in different indicators on telomere length over time. Therefore, the aim of this study is to elucidate the impact of changes in adipocyte factors, HOMA-IR, and other indicators on the dynamic variation of telomere length.

METHODS

The data were from a cohort study conducted in Ningxia, China. A total of 1624 subjects were analyzed. Adipokines and relative leukocyte telomere length (RLTL) were measured, and changes in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Homeostatic Model Assessment for β-Cell Function (HOMA-β), and Quantitative Insulin Sensitivity Check Index (QUICKI) were calculated. Generalized linear models evaluated associations between changes in adipokines and RLTL changes. Furthermore, univariate analyses examined the effects of changes in adipokines and insulin resistance indicators on ΔRLTL.

RESULTS

The research findings indicate that females generally have shorter telomeres compared to males. In comparison to the low-level group of Δleptin (LEP), the high-level group of ΔLEP shows a negative correlation with ΔRLTL (B=-1.32, 95% CI (-2.38, -0.27)). Even after multivariable adjustments, this relationship persists (B=-1.31, 95% CI (-2.24, -0.23)). Further analysis reveals that after adjusting for ΔHOMA-IR, ΔHOMA-β, and ΔQUICKI, the high-level group of ΔLEP still exhibits a significant negative correlation with ΔRLTL (B=-1.37, 95% CI (-2.43, -0.31)). However, the interaction effects between ΔHOMA-IR, ΔHOMA-β, ΔQUICKI, and ΔLEP do not affect ΔRLTL.

CONCLUSIONS

Elevated levels of leptin were significantly correlated with shortened telomere length. This suggests that increased leptin levels may impact overall individual health by affecting telomere length, underscoring the importance of measures to reduce leptin levels to mitigate the onset and progression of related diseases.

Optimization of Naringenin-loaded nanoparticles for targeting of Vanin-1, iNOS, and MCP-1 signaling pathway in HFD-induced obesity

Naringenin, a natural dihydrochalcone flavonoid, exhibits diverse pharmacological properties. This study investigates the hypolipidemic effects of Nar-NPs on obese mice. The characteristics of Nar-NPs, including morphology, particle size, zeta potential, UV-vis, and FT-IR spectra, were examined. The anti-obesity properties of Nar-NPs were evaluated in obese rats, considering LD50, 1/20 LD50, and 1/50 LD50 for treatment preparation. Results indicated that synthesized Nar-NPs were uniform, spherical, and well-dispersed, with a size of 130.06 ± 1.98 nm and with a zeta potential of -25.6 ± 0.8 mV. Nar-NPs exhibited enhancement in the cumulative release of naringenin (56.87 ± 2.45 %) as compared to pure naringenin suspension 87.83 ± 1.84 % in 24 h of the study. The LD50 of Nar-NPs was determined as 412.5 mg/kg.b.w. HFD induced elevated glycemic, oxidative stress, and inflammatory biomarkers while reducing HDL-C, GSH, and superoxide dismutase (SOD) levels. Administration of Nar-NPs significantly mitigated body weight, glucose, insulin, leptin, TC, TG, SREBP1c, pAMPK, PPAR-α, as well as vanin-1, MCP-1, and iNOS mRNA gene expression. Histological investigations supported the biochemical and PCR findings. In a nutshell, the study suggests that the Nar-NPs could serve as a promising and viable pharmacological strategy for the treatment of obesity-related disorders.

Leptin signalling regulates transcriptional differences in granulosa cells from genetically obese mice but not the activation of NLRP3 inflammasome

Obesity is associated with increased ovarian inflammation and the establishment of leptin resistance. We presently investigated the role of impaired leptin signalling on transcriptional regulation in granulosa cells (GCs) collected from genetically obese mice. Furthermore, we characterised the association between ovarian leptin signalling, the activation of the NOD-like receptor protein 3 (NLRP3) inflammasome and macrophage infiltration in obese mice. After phenotype characterisation, ovaries were collected from distinct group of animals for protein and mRNA expression analysis: (i) mice subjected to a diet-induced obesity (DIO) protocol, where one group was fed a high-fat diet (HFD) and another a standard chow diet (CD) for durations of 4 or 16 weeks; (ii) mice genetically deficient in the long isoform of the leptin receptor (ObRb; db/db); (iii) mice genetically deficient in leptin (ob/ob); and (iv) mice rendered pharmacologically hyperleptinemic (LEPT). Next, GCs from antral follicles isolated from db/db and ob/ob mice were subjected to transcriptome analysis. Transcriptional analysis revealed opposing profiles in genes associated with steroidogenesis and prostaglandin action between the genetic models, despite the similarities in body weight. Furthermore, we observed no changes in the mRNA and protein levels of NLRP3 inflammasome components in the ovaries of db/db mice or in markers of M1 and M2 macrophage infiltration. This contrasted with the downregulation of NLRP3 inflammasome components and M1 markers in ob/ob and 16-wk HFD-fed mice. We concluded that leptin signalling regulates NLRP3 inflammasome activation and the expression of M1 markers in the ovaries of obese mice in an ObRb-dependent and ObRb-independent manner. Furthermore, we found no changes in the expression of leptin signalling and NLRP3 inflammasome genes in GCs from db/db and ob/ob mice, which was associated with no effects on macrophage infiltration genes, despite the dysregulation of genes associated with steroidogenesis in homozygous obese db/db. Our results suggest that: (i) the crosstalk between leptin signalling, NLRP3 inflammasome and macrophage infiltration takes place in ovarian components other than the GC compartment; and (ii) transcriptional changes in GCs from homozygous obese ob/ob mice suggest structural rearrangement and organisation, whereas in db/db mice the impairment in steroidogenesis and secretory activity.

Exploring the impact of lifestyle and environmental exposures on appetite hormone levels in children and adolescents: An observational study

BACKGROUND

Appetite hormones are considered a promising target in fighting obesity as impaired appetite hormone levels have already been associated with obesity. However, further insights in the drivers of appetite hormone levels are needed.

OBJECTIVES

In this study, we investigated the associations of fasting appetite hormone levels with lifestyle and environmental exposures in children and adolescents.

METHODS

A total of 534 fasting blood samples were collected from children and adolescents (4-16y,50% boys) and appetite hormone levels (glucagon-like peptide-1 (GLP-1), peptide YY (PYY), pancreatic polypeptide (PP), leptin and ghrelin) were measured. Exposures included dietary quality (fiber-rich food intake, sugar propensity, fat propensity), psychosocial stress (happiness, negative emotions, negative life events and emotional problems), sleep duration, physical activity and environmental quality (long term black carbon (BC), particulate matter <2.5 μM (PM2.5), nitrogen dioxide (NO2) exposure, and green space in a 100 m and 2000 m radius around the residence). A multi-exposure score was calculated to combine all the exposures at study in one measure. Associations of individual exposures and multi-exposure score with appetite hormone levels were evaluated using linear mixed regression models adjusting for sex, age, socioeconomic status, waist-to-height ratio and multiple testing.

RESULTS

GLP-1 was associated with air pollution exposure (NO2 β* = -0.13, BC β* = -0.15, PM2.5 β* = -0.16, all p < 0.001). Leptin was associated with green space in a 100 m radius around the residence (β* = -0.11; p = 0.002). Ghrelin was associated with negative emotions (active ghrelin β* = -0.16; p = 0.04, total ghrelin β* = -0.23; p = 0.0051) and happiness (active ghrelin β* = 0.25; p < 0.001, total ghrelin β* = 0.26; p < 0.001). Furthermore, total ghrelin levels were associated with the multi-exposure score, reflecting unhealthy exposures and lifestyle (β* = -0.22; p = 0.036).

DISCUSSION

Our findings provide new insights into the associations of exposures with appetite hormone levels, which are of high interest for preventive obesity research. Further research is crucial to reveal the underlying mechanisms of the observed associations.

The causal impact of gut microbiota on circulating adipokine concentrations: a two-sample Mendelian randomization study

PURPOSE

Evidence from previous experimental and observational research demonstrates that the gut microbiota is related to circulating adipokine concentrations. Nevertheless, the debate as to whether gut microbiome composition causally influences circulating adipokine concentrations remains unresolved. This study aimed to take an essential step in elucidating this issue.

METHODS

We used two-sample Mendelian randomization (MR) to causally analyze genetic variation statistics for gut microbiota and four adipokines (including adiponectin, leptin, soluble leptin receptor [sOB-R], and plasminogen activator inhibitor-1 [PAI-1]) from large-scale genome-wide association studies (GWAS) datasets. A range of sensitivity analyses was also conducted to assess the stability and reliability of the results.

RESULTS

The composite results of the MR and sensitivity analyses revealed 22 significant causal associations. In particular, there is a suggestive causality between the family Clostridiaceae1 (IVW: β = 0.063, P = 0.034), the genus Butyrivibrio (IVW: β = 0.029, P = 0.031), and the family Alcaligenaceae (IVW: β=-0.070, P = 0.014) and adiponectin. Stronger causal effects with leptin were found for the genus Enterorhabdus (IVW: β=-0.073, P = 0.038) and the genus Lachnospiraceae (NK4A136 group) (IVW: β=-0.076, P = 0.01). Eight candidate bacterial groups were found to be associated with sOB-R, with the phylum Firmicutes (IVW: β = 0.235, P = 0.03) and the order Clostridiales (IVW: β = 0.267, P = 0.028) being of more interest. In addition, the genus Roseburia (IVW: β = 0.953, P = 0.022) and the order Lactobacillales (IVW: β=-0.806, P = 0.042) were suggestive of an association with PAI-1.

CONCLUSION

This study reveals a causal relationship between the gut microbiota and circulating adipokines and may help to offer novel insights into the prevention of abnormal concentrations of circulating adipokines and obesity-related diseases.

Obesity: An Impact with Cardiovascular and Cerebrovascular Diseases

The authors sought to correlate the complex sequel of obesity with various parameters known to develop metabolic syndrome viz. insulin resistance, dyslipidemia, hypertension etc., as these anomalies are linked to vascular atherosclerosis and outbreak of cardiovascular and cerebrovascular diseases.  A comprehensive online survey using MEDLINE, Scopus, PubMed and Google Scholar was conducted for relevant journals from 1970 till present time (2023) with key search terms like: 'obesity', 'leptin', type-2 diabetes', 'atherosclerosis', 'cardiovascular and cerebrovascular diseases'. The findings of the reports were compared and correlated. The information was then collated for developing this review. Reports showed that in human obesity, hyper-leptinemia could induce hyperglycemia, which in turn templates hypercholesterolemia. Persisting hypercholesterolemia over a period of time may en-route atherosclerosis in blood vessels. Thus obesity has been considered as a template for originating hyperglycemia, hypercholesterolemia and outbreak of vascular atherogenesis or in other words, obesity in long run can trigger atherosclerosis and its related disorders e.g. heart attack and stroke. Literature survey shows that primarily, co-morbidities of human obesity start with leptin and insulin resistance and then multiplies with metabolic irregularities to an extreme that results in pathogenesis of heart attack and stroke. Atherosclerosis associated cardiovascular and cerebrovascular events are independent risks of obese subjects and particularly in the cases of persisting obesity.

The role of hyperleptinaemia and low values of interleukin 10 in de novo DSA production after kidney transplantation

BACKGROUND

White adipose tissue secretes a number of peptide hormones. The aim of this paper was to determine the role of leptin, adiponectin and interleukin-10 and interleukin-6 on the development of graft rejection in protocol biopsy after kidney transplantation.

METHODS

In a prospective analysis (n = 104), we monitored the values of leptin, adiponectin, IL-6, and IL-10 prior to the transplantation and in the 3rd month after the transplantation. The protocol biopsy of the graft was performed in the 3rd month after the transplantation. The group was divided into the following according to the biopsy result: negative result, IFTA 1, borderline, and DSA positive.

RESULTS

After adjusting for the differences in the baseline recipient and donor characteristics, we identified the hyperleptinaemia baseline (HR = 2.0444, P = 0.0341) and month 3 (HR = 49.8043, P < 0.0001) as independent risk factors for borderline changes in the protocol biopsy. The hyperleptinaemia baseline (HR = 7.4979, P = 0.0071) and month 3 (HR = 9.7432, P = 0.0057) are independent risk factors for de novo DSA positivity. A low value of IL-10 month 3 is a risk factor for de novo DSA positivity (HR = 3.0746, P = 0.0388).

CONCLUSIONS

Higher leptin levels and low values of IL-10 might play a role in rejection and de novo DSA production.

Effects of exposure to environmental factors on obesity-related growth parameters and leptin (LEP) methylation in children

The prevalence of childhood obesity is rapidly increasing. Therefore, gaining more information on the role of environmental parameters is key. With overexpression of leptin (encoded by LEP) in obesity, LEP methylation might be altered by environmental exposures. This study aims to assess effects of ambient air pollution and nearby greenness on obesity-related growth and LEP methylation in early childhood. We monitored 120 mother-child pairs from conception until the age of five. Buccal swabs and anthropometric measurements of the children were taken at six months, one year, and five years old. Buccal DNA was extracted to determine LEP methylation levels. Estimates of air pollution and nearby greenness were calculated using high-resolution models. Effects of air pollution and nearby greenness on growth or LEP methylation were investigated using linear mixed effects models. Positive associations were shown for air pollution between conception and age one on impedance in six-month-olds and one-year-olds in the crude model. PM with aerodynamic diameter ≤10 (PM10) and ≤2.5 μm (PM2.5) positively associated with waist-hip-ratio and waist circumference at age five in the fully adjusted model. In early childhood, closest distance to forest negatively, and urban green and forest positively associated with weight-for-length, body mass index, and fat percentage in five-year-olds in the fully adjusted model. No significant associations for noise, and walkability on growth were seen. Negative associations were shown for smaller green clusters and positive associations for greater green clusters on LEP methylation in one-year-olds. For forest distance, walkability, noise, or all green on LEP methylation, no significant associations were found. Evidence is provided that ambient air pollution might have a significant effect on impedance and waist-hip-ratio, suggesting an increased risk of childhood obesity. Based on LEP methylation, greater green clusters might associate with a decreased risk of childhood obesity, while smaller green clusters showed the opposite.

Body weight variation is not an independent factor in the determination of functional hypothalamic amenorrhea in anorexia nervosa

OBJECTIVE

Functional hypothalamic amenorrhea (FHA) is one of the foremost manifestations in anorexia nervosa (AN), but a subset of patients have menses despite marked weight loss and underweight. The aim of our study was to investigate parameters potentially influencing FHA in AN.

DESIGN AND METHODS

In this observational retrospective study, we selected 114 female patients with AN who completed a 12 months semi-residential rehabilitation program and a subsequent 12 months outpatient follow-up. We divided our sample into three groups: "Group 0" patients who experienced FHA and recovered their menses, "Group 1" persistent FHA, "Group 2" never experienced FHA, and looked for clinical and hormonal correlations.

RESULTS

At the enrollment, the BMI was higher in Group 2 than in Group 1 (p = 0.0202), but the last follow-up weight was higher in Group 1 (p < 0.0001) despite persistent amenorrhea. At logistic regression, the higher BMI at which patients experienced amenorrhea was the main prediction factor for persistent FHA. Notwithstanding comparable leptin levels at admission, they improved significantly at discharge only in Groups 0 and 2 (p = 0.0054 and p = 0.0104, respectively). FT3 at admission was significantly higher in Group 2 than in Group 0 (p = 0.0249).

CONCLUSIONS

FHA does not correlate strictly with body weight variations in AN patients, indicating a multifactorial origin, likely including an individual predisposition. Higher FT3 levels identify patients who continue having menses at extremely low BMI. AN patients with persistent FHA constitute a subgroup in whom estroprogestins should be considered after significant weight recovery to prevent prolonged tissue hypoestrogenism.

Adiponectin/leptin ratio predicts the remission of metabolic syndrome: A pilot study

BACKGROUND

Adipokines are key mediators of inflammation in metabolic syndrome perpetuating the effect of excess nutrient intake by setting a self-maintaining vicious circle. Here, we assess levels of adiponectin and leptin in a cohort of individuals with MetS undergoing dietary and behavioral counselling. Specifically, we investigate their role as predictors of metabolic syndrome remission after 1 year.

METHODS

Patients with MetS (n = 127) received behavioral and dietary recommendations and were followed-up for 1 year. Serum was available for 108 individuals, levels of adiponectin and leptin were tested at baseline, at 6 months (t1) and after 1 year (t2). Adiponectin/leptin (A/L) ratio was also calculated and tested for predictive ability.

RESULT

At the end of the follow-up period, 59 patients did not show enough criteria to define MetS anymore. When considered alone, adiponectin and leptin levels did not show difference over follow-up. Their ratio instead was significantly reduced at t1 and t2 with respect to baseline. Remitters also showed lowers level of leptin and A/L ratio as compared to non-remitters at t1. At this timepoint, A/L ratio independently predicted MetS remission at 1 year [OR 9.082 95%CI (1.394-59.160), p = 0.021]. Bootstrap resampling analysis internally validated our findings.

CONCLUSIONS

Preliminary results from our pilot study suggest that MetS remission after counselling associates with changes in adipokine balance. A/L ratio decreases overtime and its value at 6 months can independently predict MetS remission.

Differences in metabolic biomarkers in people with schizophrenia who are of Mexican descent compared to non-Hispanic whites

Metabolic dysfunction is highly prevalent and contributes to premature mortality among people with schizophrenia (PwS), especially in Hispanic/Latino/a/x/e PwS, compared to non-Hispanic White (NHW) PwS. This study evaluated the relative contributions of Mexican descent and schizophrenia diagnosis to metabolic biomarker levels. This cross-sectional study included 115 PwS and 102 non-psychiatric comparison (NC) participants - English-speakers aged 26-66 years, 27% Mexican descent, and 52% women across both groups. Assessments included evaluations of BMI, psychopathology, and fasting metabolic biomarkers. We used ANOVA analyses to compare metabolic outcomes between diagnostic and ethnic subgroups, linear regression models to examine associations between Mexican descent and metabolic outcomes, and Spearman's correlations to examine relationships between metabolic outcomes and illness-related variables in PwS. Mexican PwS had higher hemoglobin A1c levels, insulin resistance, and body mass index than NHW PwS. Mexican descent was associated with higher hemoglobin A1c levels, insulin resistance, body mass index, and leptin levels, controlling for age, sex, depression, education, and smoking. Among Mexican PwS, worse negative symptoms were associated with greater insulin resistance. These findings support the possibility of ethnicity-based differences in metabolic dysregulation, though further investigation is warranted to create targeted health interventions for Hispanic PwS.

The effect of curcumin supplementation on circulating adiponectin and leptin concentration in adults: a GRADE-assessed systematic review and meta-analysis of randomised controlled trials

Curcumin is a phytocompound found in the root of turmeric, a common herbal ingredient in many Asian cuisines. The compound contains anti-inflammatory activity, which is mediated through an upregulation of adiponectin and reduction of leptin. Results of randomised controlled trials (RCT) have shown that the effects of curcumin on adipokines are conflicting. Therefore, the current systematic review and meta-analysis of RCT were conducted with the aim of elucidating the role of curcumin supplementation on serum adiponectin and leptin. The search included PubMed, Embase, Cochrane Library, Scopus, Web of Science and Google Scholar from inception to August 2023. For net changes in adipokines, standardised mean differences (SMD) were calculated using random effects models. Thirteen RCT with fourteen treatment arms were eligible for inclusion in this meta-analysis. Curcumin supplementation was effective in increasing serum adiponectin (SMD = 0·86, 95 % CI (0·33, 1·39), P < 0·001; I2 = 93·1 %, P < 0·001) and reducing serum leptin (SMD = -1·42, 95 % CI (-2·29, -0·54), P < 0·001; I2 = 94·7 %, P < 0·001). In conclusion, curcumin supplementation significantly increased circulating adiponectin and decreased leptin levels in adults.

Proceedings of the annual meeting of the European Consortium of Lipodystrophies (ECLip), Pisa, Italy, 28-29 September 2023

Lipodystrophy syndromes are rare diseases primarily affecting the development or maintenance of the adipose tissue but are also distressing indirectly multiple organs and tissues, often leading to reduced life expectancy and quality of life. Lipodystrophy syndromes are multifaceted disorders caused by genetic mutations or autoimmunity in the vast majority of cases. While many subtypes are now recognized and classified, the disease remains remarkably underdiagnosed. The European Consortium of Lipodystrophies (ECLip) was founded in 2014 as a non-profit network of European centers of excellence working in the field of lipodystrophies aiming at promoting international collaborations to increase basic scientific understanding and clinical management of these syndromes. The network has developed a European Patient Registry as a collaborative research platform for consortium members. ECLip and ECLip registry activities involve patient advocacy groups to increase public awareness and to seek advice on research activities relevant from the patients perspective. The annual ECLip congress provides updates on the research results of various network groups members.

Amelioration of obesity induction by a high-fat diet and related inflammation by Phasa fish (Setipinna phasa) oil in BALB/c mice

We have extracted and characterized Phasa fish (Setipinna phasa) oil for the first time to evaluate the anti-obesity and related anti-inflammatory effects on obese mice. Inbred male albino BALB/c mice were segregated into three categories: control (C), Obese control group (OC), and Phasa fish oil treated group (TX). To establish the potentiality of Setipinna phasa oil for its anti-obesity and anti-inflammatory properties, it was extracted and characterized using GC-MS method. To evaluate the anti-obesity effect, different parameters were considered, such as body weight, lipid composition, obesity, and obesity associated inflammation. The physicochemical characteristics of Phasa fish oil revealed that the oil quality was good because acid value, peroxide value, p-anisidine value, Totox value, refractive index, and saponification value were within the standard value range. The GC-MS study explored the presence of fatty acids beneficial to health such as Hexadec-9-enoic acid; Octadec-11-enoic acid; EPA, DHA, Methyl Linolenate, etc. The application of Setipinna phasa oil on the treated mice group acutely lowered body weight and serum lipid profile compared to the obese group. In connection with this, leptin, FAS, and pro-inflammatory cytokines TNF-α genes expression were downregulated in the treated group compared to the obese group. The Phasa oil treated group had an elevated expression of PPAR-α, adiponectin, LPL gene, and anti-inflammatory markers IL-10 and IL-1Ra compared to the obese group. This study suggests that Phasa fish oil, enriched with essential fatty acid, might be used as an anti-obesity and anti-inflammatory supplement.

Association of Leptin with Glucose Intolerance and Gestational Diabetes Mellitus in Pregnant Women: Prospective Analytical Case-Control Study

This study aimed to investigate the use of leptin as a marker for gestational diabetes by analyzing any correlation between serum leptin levels versus oral glucose tolerance tests (at 24 to 28 weeks of pregnancy) and increased body weight (during pregnancy). A total of 110 female cases (81 pregnant and 29 non-pregnant) were included in the study. The 81 pregnant cases were divided into 3 groups according to their oral glucose tolerance test results. A chi-square test was used for categorical variables. The distribution of numerical variables was tested with the Shapiro-Wilk test. ANOVA and a post-hoc Bonferroni test was used for parametric data. Kruskal-Wallis variance analysis was used for non-parametric data. The Mann-Whitney U-test was used for pairwise comparisons. Spearman correlation analysis and multivariate regression analysis were performed for the evaluation of the correlation analysis between the parameters. Oral glucose tolerance test results were compared with leptin levels with a cut-off value of 11.43 for leptin. The ROC curve demonstrated an 83.3% sensitivity and 72.1% specificity for leptin. Leptin may play a role in the pathophysiology of gestational diabetes mellitus. However, the relationship between leptin levels and maternal weight gain during pregnancy is still unknown.

Association between blood hormones and fecundity in rabbit does

The aim of the present study was to examine the association between blood hormone level and fecundity in rabbit does. The ovulation of nulliparous New Zealand White rabbits was induced by administration of PMSG and LH-RH analogue. Next day, the does were inseminated, blood was collected and the plasma levels of IGFI, leptin, progesterone and estradiol were measured by radioimmunoassay. After the birth of pups, the retrospective comparison of level of hormones in the blood of fertile and non-fertile animals was performed. Fertile does had significantly higher blood level of IGF-I and lower concentration of leptin than the infertile ones. No significant differences in blood progesterone and estradiol level was found between fertile and non-fertile females. These observations suggest that blood IGF-I and leptin level could be useful for diagnostics and prediction of rabbit does' fecundity.

Acute nicotine intake increases feeding behavior through decreasing glucagon signaling in dependent male and female rats

Chronic use of nicotine is known to dysregulate metabolic signaling through altering circulating levels of feeding-related hormones, contributing to the onset of disorders like type 2 diabetes. However, little is known about the acute effects of nicotine on hormonal signaling. We previously identified an acute increase in food intake following acute nicotine, and we sought to determine whether this behavior was due to a change in hormone levels. We first identified that acute nicotine injection produces an increase in feeding behavior in dependent rats, but not nondependent rats. We confirmed that chronic nicotine use increases circulating levels of insulin, leptin, and ghrelin, and these correlate with rats' body weight and food intake. Acute nicotine injection in dependent animals decreased circulating GLP-1 and glucagon levels, and administration of glucagon prior to acute nicotine injection prevented the acute increase in feeding behavior. Thus, acute nicotine injection increases feeding behavior in dependent rats by decreasing glucagon signaling.

PCSK9 and leptin plasma levels in anorexia nervosa

AIM

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a regulator of low-density-lipoprotein cholesterol (LDL-C), a major risk factor for cardiovascular (CV) disease. Since the hormone leptin has been suggested as having a role in CV risk regulation, possibly by modulating LDL receptor expression through the PCSK9 pathway, nutritional status may represent a potential regulator. Thus, evaluation of PCSK9 levels in human eating disorders appears to be of interest. In this report, we evaluate the lipoprotein profile, PCSK9, and leptin levels in subjects affected by anorexia nervosa (AN) to improve our understanding of the metabolic alterations in this disease.

METHODS AND RESULTS

We designed a case-control observational study, enrolling 20 anorexic adolescent females and 20 adolescent females without AN as the control group, age- and sex-matched. Subjects affected by AN showed lower BMI, total cholesterol, and LDL-C in comparison to the control group, with lipoprotein levels in the normal range. Furthermore, adolescent girls with AN show significantly higher PCSK9 (+24%, p < 0.005) and lower leptin levels (-43%, p < 0.01), compared to the control group.

CONCLUSIONS

The findings of increased levels of PCSK9 and reduced leptin levels among AN subjects warrant further research in order to unravel the role of the liver and adipose tissue in the management of PCSK9/LDL metabolism in adolescents affected by AN.

Exploring the folding landscape of leptin: Insights into threading pathways

The discovery of new protein topologies with entanglements and loop-crossings have shown the impact of local amino acid arrangement and global three-dimensional structures. This phenomenon plays a crucial role in understanding how protein structure relates to folding and function, affecting the global stability, and biological activity. Protein entanglements encompassing knots and non-trivial topologies add complexity to their folding free energy landscapes. However, the initial native contacts driving the threading event for entangled proteins remains elusive. The Pierced Lasso Topology (PLT) represents an entangled topology where a covalent linker creates a loop in which the polypeptide backbone is threaded through. Compared to true knotted topologies, PLTs are simpler topologies where the covalent-loop persists in all conformations. In this work, the PLT protein leptin, is used to visualize and differentiate the preference for slipknotting over plugging transition pathways along the folding route. We utilize the Energy Landscape Visualization Method (ELViM), a multidimensional projection technique, to visualize and distinguish early threaded conformations that cannot be observed in an in vitro experiment. Critical contacts for the leptin threading mechanisms were identified where the competing pathways are determined by the formation of a hairpin loop in the unfolded basin. Thus, prohibiting the dominant slipknotting pathway. Furthermore, ELViM offers insights into distinct folding pathways associated with slipknotting and plugging providing a novel tool for de novo design and in vitro experiments with residue specific information of threading events in silico.

Relationship of bisphenol A substitutes bisphenol F and bisphenol S with adiponectin/leptin ratio among children from the environment and development of children cohort

BACKGROUND

Bisphenol A (BPA) is known as an obesogenic endocrine disruptor. Bisphenol S (BPS) and F (BPF) are substitutes that have recently replaced BPA.

OBJECTIVES

To investigate the relationships of urinary bisphenols (BPA, BPS and BPF) with adiposity measurements (obesity, BMI z-score, and fat mass), serum adipokine levels (adiponectin and leptin), and adiponectin/leptin ratio (A/L ratio) in 6- and 8-year-old children.

METHODS

A total of 561 children who participated in the Environment and Development of Children cohort (482 and 516 children visited at age 6 and 8, respectively) at Seoul National University Children's Hospital during 2015-2019 were included. Urinary BPA levels were log-transformed. BPS levels were categorized into three groups (non-detected, lower-half, and higher-half of detected), and BPF levels were classified into two groups (non-detected and detected).

RESULTS

The urinary BPS higher-half group had a higher BMI z-score (β = 0.160, P= 0.044), higher fat mass (β = 0.104, P< 0.001), lower adiponectin concentration (β =- 0.069, P< 0.001), higher leptin concentration (β = 0.360, P< 0.001), and lower A/L ratio (β =- 0.428, P< 0.001) compared with the non-detected group. The urinary BPF-detected group had a higher fat mass (β = 0.074, P< 0.001), lower adiponectin concentration (β =- 0.069, P< 0.001), higher leptin concentration (β = 0.360, P< 0.001), and lower A/L ratio (β =- 0.428, P< 0.001) compared with the non-detected group. The BPA levels showed no consistent associations with outcomes, except for isolated associations of BPA at age 6 with a higher BMI z-score at age 6 (P= 0.016) and leptin at age 8 (P= 0.021).

CONCLUSIONS

Increased exposure to BPS and BPF is associated with higher fat mass and leptin concentration, lower serum adiponectin, and lower A/L ratio in children. These findings suggest potential adverse effects of BPA substitutes on adiposity and adipokines. No consistent association of BPA exposure with outcomes could be partly explained by the decreasing BPA levels over time.

Baroreflex afferent function is a part of insights of Leptin-mediated blood pressure reduction and Leptin-resistance hypertension

The aim of this study is to verify the impact of Leptin in blood pressure (BP) regulation and Leptin-resistance in metabolic/neurogenic hypertension through baroreflex afferents and dysregulation. Artery BP/heart rate (HR) were measured while nodose (NG) microinjection of Leptin, membrane depolarization/inward current were obtained by whole-cell patch from NG neurons isolated from adult female rats. Baroreflex sensitivity (BRS) tested with PE/SNP, distribution/expression of Leptin/receptors in the NG/nucleus tractus solitary (NTS) examined using immumostaining and qRT-PCR, and serum concentrations of Leptin/NE measured by ELISA were observed in control and high fructose-drinking induced hypertension (HTN-HFD) rats. The results showed that BP was significantly/dose-dependently reduced by Leptin NG microinjection likely through direct excitation of female-specific subpopulation of Ah-type neurons showing a potent membrane depolarization/inward currents. Sex-specific distribution/expression of OB-Ra/OB-Rb in the NG were detected with estrogen-dependent manner, similar observations were also confirmed in the NTS. As expected, BRS was dramatically decreased in the presence of PE/SNP in both male and female rats except for the female with PE at given concentrations. Additionally, serum concentration of Leptin was elevated in HFD-HTN model rats of either sex with more obvious in females. Under hypertensive condition, the mean fluorescent density of OB-R and mRNA expression for OB-Ra/OB-Rb in the NG/NTS were significantly down-regulated. These results have demonstrated that Leptin play a role in dominant parasympathetic drive via baroreflex afferent activation to buffer Leptin-mediated sympathetic activation systemically and Leptin-resistance is an innegligible mechanism for metabolic/neurogenic hypertension through baroreflex afferent dysregulation.

Serum levels of adiponectin differentiate generalized lipodystrophies from anorexia nervosa

PURPOSE

The differential diagnosis of lipodystrophy involves other disorders characterized by severe fat loss and may be sometimes challenging. Owing to the rarity of lipodystrophy, it is relevant to search for tools and assays that differentiate it from other diseases that may mimic it. We conducted a study on leptin and high molecular weight (HMW) adiponectin serum concentrations in a series of patients diagnosed with lipodystrophy and compared them with those found in anorexia nervosa, one of the illnesses that may be cause of a missed diagnosis of lipodystrophy.

METHODS

Leptin and HMW adiponectin serum concentrations were measured in six patients diagnosed with generalized lipodystrophy (GL), six with progeroid syndromes (PS), 13 with familial partial lipodystrophy type 1 (FPLD1, Kobberling syndrome), 10 with familial partial lipodystrophy type 2 (FPLD2, Dunnigan syndrome), 18 with acquired partial lipodystrophy (APL) and 12 affected by anorexia nervosa (AN). Measurements were compared to those obtained in 12 normal weight healthy subjects.

RESULTS

Serum leptin concentrations were reduced to a similar degree in GL, PS and AN, proportionally to the extent of fat loss. Serum concentrations of HMW adiponectin were found extremely low in patients with GL and PS, while comparable to normal weight subjects in patients with AN.

CONCLUSION

Serum HMW adiponectin can be regarded as a useful tool to discriminate between generalized lipodystrophy syndromes (including PS) and AN.

Linking adipose tissue eosinophils, IL-4, and leptin in human obesity and insulin resistance

BACKGROUNDObesity is a multifactorial disease with adverse health implications including insulin resistance (IR). In patients with obesity, the presence of high circulating levels of leptin, deemed hyperleptinemia, is associated with IR. Recent data in mice with diet-induced obesity (DIO) show that a partial reduction in leptin levels improves IR. Additional animal studies demonstrate that IL-4 decreases leptin levels. In rodents, resident adipose tissue eosinophils (AT-EOS) are the main source of IL-4 and are instrumental in maintaining metabolic homeostasis. A marked reduction in AT-EOS content is observed in animal models of DIO. These observations have not been explored in humans.METHODSWe analyzed AT from individuals with obesity and age-matched lean counterparts for AT-EOS content, IL-4, circulating leptin levels, and measures of IR.RESULTSOur results show that individuals with obesity (n = 15) had a significant reduction in AT-EOS content (P < 0.01), decreased AT-IL-4 gene expression (P = 0.02), and decreased IL-4 plasma levels (P < 0.05) in addition to expected IR (P < 0.001) and hyperleptinemia (P < 0.01) compared with lean subjects (n = 15). AT-EOS content inversely correlated with BMI (P = 0.002) and IR (P = 0.005). Ex vivo AT explants and in vitro cell culture of primary human mature adipocytes exposed to either IL-4 or EOS conditioned media produced less leptin (P < 0.05).CONCLUSIONOur results suggest that IL-4 acts as a link between EOS, AT, and leptin production. Future studies exploring this interaction may identify an avenue for the treatment of obesity and its complications through amelioration of hyperleptinemia.TRIAL REGISTRATIONClinicaltrials.gov NCT02378077 & NCT04234295.

Effect of Fibrate Treatment on Circulating Adipokine Levels: A Systematic Review and Meta-analysis of Randomized Clinical Trials

BACKGROUND

Fibrates are widely used in the treatment of dyslipidemia and associated metabolic abnormalities; however, their effects on adipokines are unclear.

AIM OF THE STUDY

This meta-analysis of clinical trials aimed to evaluate the effect of fibrates on circulating adipokine levels.

METHODS

Only randomized controlled trials investigating the impact/effect of fibrate treatment on circulating adipokine levels were included from searches in PubMed-Medline, SCOPUS, ClinicalTrials.gov, Web of Science, and Google Scholar databases. A random effects model and the generic inverse variance method were used for the meta-analysis. Sensitivity analysis was conducted using the leave-one-out method.

RESULTS

This meta-analysis of 22 clinical trials showed a significant reduction on/in leptin (WMD: -1.58 ng/mL, 95% CI: -2.96, -0.20, p = 0.02, I2 = 0%), plasminogen activator inhibitor-1 (PAI-1) (WMD: -13.86 ng/mL, 95% CI: -26.70, -1.03, p = 0.03, I2 = 99%), and visfatin (WMD: -1.52 ng/mL, 95% CI: -2.49, -0.56, p = 0.002, I2 = 0%) after fibrate therapy; no significant effect was observed on adiponectin (WMD: -0.69 µg/ml, 95% CI: -1.40, 0.02, p = 0.06, I2 = 83%) and resistin (WMD: -2.27 ng/mL, 95% CI: -7.11, 2.57, p = 0.36, I2 = 0%). The sensitivity analysis was robust only for visfatin, while the effect size was sensitive to one arm for leptin, four for adiponectin, and two for PAI-1.

CONCLUSION

This meta-analysis showed that fibrate treatment significantly improves adipokine levels with a decrease in leptin, PAI-1, and visfatin, suggesting potential additional clinical therapeutic benefits through/of fibrate treatment on adipose tissue.

Association of polymorphism in leptin receptor gene with susceptibility of adolescent idiopathic scoliosis

PURPOSE

Abnormal leptin bioavailability has play key roles in the etiology of adolescent idiopathic scoliosis (AIS). Both leptin and its receptor levels may be modulated by the presence of genetic polymorphisms. This study aimed to evaluate the role of polymorphisms in the leptin (LEP) and its main receptor (LEPR) genes in the AIS susceptibility in girls.

METHODS

A retrospective case-control study was conducted with 189 AIS and 240 controls. LEP rs2167270 and LEPR rs2767485 polymorphisms were genotyped using a TaqMan validated assay. Associations were evaluated by odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

The AIS group showed a predominance of girls under 18 years old (n = 140, 74.1%), 148 (78.3%) had low or normal BMI, 111 (58.7%) had Cobb ≥ 45º and 130 (68.7%) were skeletally mature. Minor allele frequencies of rs2167270 and rs2767485 were 35.7% and 18.3%, for AIS and 35.6% and 25.4% for controls, respectively. LEPR rs2767485 T and TC + TT were associated with higher risk of AIS (OR = 1.53; 95% CI = 1.09-2.13 and OR = 1.84; 95% CI = 1.69-2.01, respectively), since CC genotype was only present in the control group. In addition, the LEP rs2167270 GA + AA was more frequent in low weight group (BMI ≤ 24.9) of girls with AIS. There was no significant association between LEP rs2167270 and AIS susceptibility, and LEPR rs2767485 and BMI.

CONCLUSION

The LEPR rs2767485 was associated with the genetic susceptibility of AIS and LEP rs2167270 with low BMI. These data can contribute to the identification of genetic biomarkers to improve the diagnosis and treatment.

Twenty-four-hour ambulatory, but not clinic blood pressure associates with leptin in young adults with overweight or obesity: The African-PREDICT study

Hypertension and obesity are known pro-inflammatory conditions, and limited studies explored various blood pressure modalities and inflammatory markers in young adults with overweight or obesity (OW/OB). We assessed the relationship of clinic and 24 h ambulatory blood pressure with an array of inflammatory markers in young adults with OW/OB. This cross-sectional study included women and men of Black and White ethnicity (n = 1194) with a median age of 24.5 ± 3.12 years. Participants were divided into normal weight and OW/OB groups according to body mass index. Clinic and 24 h ambulatory systolic and diastolic blood pressure were measured. Inflammatory markers included leptin, interleukin-6, interleukin-8, tumour necrosis factor-α, adiponectin, interleukin-10, and C-reactive protein. After adjustments for age, sex, and ethnicity, the OW/OB group had higher blood pressure and an overall worse inflammatory profile compared to the normal weight group (all p ≤ 0.024). In the OW/OB group, 24 h systolic (r = 0.22; p < 0.001) and diastolic blood pressure (r = 0.28; p < 0.001) correlated with leptin, independent of age, sex, and ethnicity. In fully adjusted regression models, 24 h systolic blood pressure (adj.R2 = 0.25; β = 0.28; p = 0.035) and diastolic blood pressure (adj.R2 = 0.10; β = 0.32; p = 0.034), associated with leptin in the OW/OB group and significance remained with additional adjustments for visceral adiposity index. Twenty-four-hour ambulatory, but not clinic blood pressure, is related to leptin in young adults with OW/OB. Leptin shows a stronger relationship with adiposity when compared to other inflammatory markers and may play a role in subcutaneous adiposity-related increased blood pressure.

Safety assessment of the SGLT2 inhibitors empagliflozin, dapagliflozin and canagliflozin during pregnancy: An ex vivo human placenta perfusion and in vitro study

Although uncontrolled hyperglycaemia during pregnancy can cause complications for both the mother and her offspring, pharmacological treatment options for gestational and type 2 diabetes in pregnancy are still limited. Empagliflozin (EMPA), dapagliflozin (DAPA) and canagliflozin (CANA) are three sodium glucose co-transporter 2 (SGLT2) inhibitors, a newer group of oral antidiabetics that are well established in the treatment of type 2 diabetes mellitus in non-pregnant patients. To date, no data regarding their placental transfer and safety in pregnant women are available. We performed ex vivo human placental perfusions (n = 4, term placentas, creatinine and antipyrine as connectivity controls) to evaluate the transplacental transfer of EMPA, DAPA and CANA across the placental barrier and assessed their influence on the secretion of two placental peptide hormones, leptin and β-human chorionic gonadotropin (β-hCG). We discovered that all three SGLT2 inhibitors cross the placental barrier and attained maximal foetal to maternal concentration ratios of 0.38 ± 0.09 (EMPA), 0.67 ± 0.05 (DAPA) and 0.62 ± 0.05 (CANA) within the tested 360 min. A moderate but statistically significant decrease in placental leptin - but not β-hCG - secretion was observed during perfusions with SGLT2 inhibitors, which was confirmed in experiments performed with human placental BeWo cells. SGLT2 inhibitors are able to cross the human placental barrier and seem to interfere with placental leptin production. These observations should be considered in the ongoing discussion on the optimal treatment for gestational diabetes and type 2 diabetes mellitus in pregnancy.

Leptin, Nesfatin-1, Orexin-A, and Total Ghrelin Levels in Drug-Naive Panic Disorder

OBJECTIVE

This study aimed to examine the changes in serum nesfatin-1, leptin, orexin-A, and total ghrelin levels of patients diagnosed with drug-naive panic disorder (PD) before and after six weeks of the treatment and to compare the findings with the healthy subjects.

METHODS

The neuropeptides were measured in venous blood samples taken from 32 patients and 32 healthy subjects. The blood samples of the patients who used paroxetine 20 mg/day plus alprazolam 0.5 mg/day were retaken again after six weeks. Measurements were performed with the Enzyme-Linked Immunosorbent Assay (ELISA) method.

RESULTS

Serum nesfatin-1, leptin, orexin-A and total ghrelin levels of the patient group were found to be significantly lower than the control group (p<0.001, p<0.001, p<0.001, and p<0.001, respectively). When the serum nesfatin-1, leptin, orexin-A and total ghrelin levels of the patient group were compared before and after treatment, significant differences were found in terms of orexin-A and total ghrelin levels (p=0.046, p<0.001, respectively). However, no significant differences were found in terms of nesfatin-1and leptin levels (p=0.205, p=0.988, respectively).

CONCLUSION

This study reports that PD, like other anxiety disorders, may affect serum nesfatin-1, leptin, orexin-A, and total ghrelin levels, and there may be a relationship between PD treatment and the levels of these neuropeptides. The variability of this relationship among the neuropeptides examined indicates that various factors other than treatment play a role in this process.

The role of leptin in ischemic stroke and its subtypes: A Mendelian randomization study

BACKGROUND AND AIMS

Observational studies have suggested a relationship between leptin and risk of stroke. However, evidence for the association remains inconsistent, and whether the association reflects a causal relationship remains to be established. To clarify this relationship, we adopted a two-sample Mendelian randomization (MR) analysis to investigate whether leptin plays a causal role in the risk of stroke and its subtypes.

METHODS AND RESULTS

Five independent single-nucleotide polymorphisms (SNPs) associated with the leptin level from genome-wide association studies (GWASs) of European individuals were selected. We performed an MR analysis using the inverse-variance-weighted (IVW) as primary method to examine the causal effects of leptin on ischemic stroke (IS). Moreover, MR-Egger intercept and Cochran's Q statistic were also performed to detect the pleiotropy or heterogeneity of our MR results. Genetically predicted circulating leptin level was not associated with ischemic stroke [odds ratio (OR): 1.48, 95% confidence interval (CI): 0.78-2.8, P = 0.22], large artery stroke (OR: 1.44, 95% CI: 0.39-5.25, P = 0.57), cardioembolic stroke (OR:1.33, 95% CI: 0.55-3.22, P = 0.52), and small vessel stroke (OR: 1.48, 95% CI: 0.39-5.63, P = 0.56) using the IVW method. Likewise, there is no convincing evidence for the associations between leptin levels and cardiovascular diseases (CVD) risk factors.

CONCLUSIONS

This study did not provide evidence that leptin levels are associated with increased risk of stroke and its subtypes.

Molecular pathways in placental-fetal development and disruption

The first trimester of pregnancy ranks high in priority when minimizing harmful exposures, given the wide-ranging types of organogenesis occurring between 4- and 12-weeks' gestation. One way to quantify potential harm to the fetus in the first trimester is to measure a corollary effect on the placenta. Placental biomarkers are widely present in maternal circulation, cord blood, and placental tissue biopsied at birth or at the time of pregnancy termination. Here we evaluate ten diverse pathways involving molecules expressed in the first trimester human placenta based on their relevance to normal fetal development and to the hypothesis of placental-fetal endocrine disruption (perturbation in development that results in abnormal endocrine function in the offspring), namely: human chorionic gonadotropin (hCG), thyroid hormone regulation, peroxisome proliferator activated receptor protein gamma (PPARγ), leptin, transforming growth factor beta, epiregulin, growth differentiation factor 15, small nucleolar RNAs, serotonin, and vitamin D. Some of these are well-established as biomarkers of placental-fetal endocrine disruption, while others are not well studied and were selected based on discovery analyses of the placental transcriptome. A literature search on these biomarkers summarizes evidence of placenta-specific production and regulation of each biomarker, and their role in fetal reproductive tract, brain, and other specific domains of fetal development. In this review, we extend the theory of fetal programming to placental-fetal programming.

Sex differences in the effects of repeated ketamine infusions on bone markers in patients with unipolar and bipolar depression

BACKGROUND

Patients with depression, especially women, are associated with low bone mineral density (BMD). Traditional antidepressants are associated with negative effects on BMD. Few studies have examined the effect of ketamine on BMD, and it remains unclear whether there are sex differences in the effects of ketamine on BMD in patients with depression.

METHODS

A total of 102 patients with unipolar and bipolar depression were administered six infusions of intravenous ketamine over a 12-day period. Plasma levels of eight bone markers were examined at baseline, 24 h after the sixth infusion and again 2 weeks (Days 13 and 26).

RESULTS

Linear mixed models showed all bone markers had significant time main effect (all p < 0.05). Compared with baseline, the whole sample showed increased levels of leptin and osteoprotegerin at Days 13 and 26, as well as Dickkopf-related protein 1 at Day 13, and decreased levels of osteocalcin, sclerostin, osteopontin, parathyroid hormone and fibroblast growth factor 23 at Days 13 and 26 (all p < 0.05). Females had a higher level of leptin at Days 13 and 26, and lower levels of osteocalcin and sclerostin at Day 13 than males (all p < 0.05). Increases of leptin were associated with depressive symptom improvements at Day 13 and Day 26 in females (both p < 0.05). In males, higher baseline osteocalcin levels were associated with greater depressive symptom improvement at Day 26 (β = 0.414, p = 0.009).

CONCLUSIONS

Our results suggest that repeated ketamine infusions may be associated with modulation of bone markers in patients with depression and present sex differences. Baseline osteocalcin level may be served as a predictor for the antidepressant effects of ketamine in males. Trial registration Data were derived from an open label clinical trial, which was registered at Chinese Clinical Trial Registry (ChiCTR-OOC-17012239). Registered 26 May 2017. http://www.chictr.org.cn.

Serum iron concentration and leptin inversely relate, partially mediated by body mass index in American adults

Iron metabolism and leptin are interconnected, and both link with obesity. In this cross-sectional study, we hypothesized that serum iron markers associate with leptin, with body mass index (BMI) acting as a mediator, confounder, and effect modifier in this relationship. We analyzed data from the National Health and Nutrition Examination Survey III, with a focus on serum iron markers and leptin. The relationship between serum iron markers and leptin was determined by multiple linear regression. The bootstrap method was used to investigate the mediating effect of BMI on this association. Among 3888 American adults, serum iron and transferrin saturation showed a negative association with leptin (log2-transformed) (β: -0.010, 95% confidence interval [CI], -0.013 to -0.006, P < .001; β: -0.006, 95% CI, -0.008 to -0.004, P < .001). Total iron-binding capacity was positively associated with the serum concentration of leptin (log2-transformed) (β: 0.002, 95% CI, 0-0.004, P = .0292). Sex, BMI, and body fat percentage significantly influenced these associations. Notably, the association between the iron markers and leptin diminished in individuals with a BMI ≥30 kg/m2. There was no observable relationship between leptin and serum ferritin concentrations. BMI mediated 4.81% of the serum iron-leptin association, with no mediation of body fat percentage. Our study identified a link between serum iron and leptin, with BMI as a mediating factor. In clinical settings, it is vital to understand how treatments targeting iron metabolism can directly impact serum leptin concentration and the subsequent physiological changes.

The effect of resistin on the redox state of breast cancer cells

PURPOSE

Resistin is an inflammatory cytokine secreted mostly by adipocytes and immune cells that plays a role in the development of insulin resistance, diabetes, and cancer. We hypothesized that resistin's inflammatory activity influences the free radical and oxidative stress pathways.

METHODS

We used human breast carcinogenic (MCF-7 and MDA-MB-231) and non-carcinogenic (MCF-10A) cells in this investigation and correlated the absorbed resistin concentration with the change in oxidative stress (TBARS, carbonated proteins) and antioxidant activity (Antioxidant Capacity, SuperOxideDismutase, CATalase, Glutathione Peroxidase).

RESULTS

Resistin was substantially more effective as a prooxidant at lower (12.5 ng/ml) concentrations, than at higher concentrations (25.0 ng/ml). Vitamin C did not appear to be an effective oxidative stress protector at antioxidant concentrations of 5.10-4 M. Leptin, at 100 ng/ml, did not result in conclusive oxidative stress or antioxidant defence stimulation, as expected.

CONCLUSION

Taken together, the findings support resistin's role as a non-oxidative stress marker and a metabolic signaling molecule.

Leptin decreases the transcription of BKCa channels and Gs to Gi protein-ratio in late pregnant rat uterus

Obesity can have a significant impact on pregnancy outcomes by compromising the ability of the uterus to relax, which increases the likelihood of conditions such as preterm labor. One of the key pathways responsible for uterine relaxation is the β-adrenergic signaling pathway, and it is well-documented that obesity, often linked to a high-fat diet, can disrupt this pathway within the uterine environment. Hyperleptinemia is a significant feature of pregnancy as well as obesity. However, the effect of leptin on β-adrenergic signaling pathway has not been studied. In the present study, we studied the effects of leptin on transcriptions of the major proteins defining the β-adrenergic signaling pathway in pregnant rat uterus. Leptin treatment at a supraphysiological concentration to pregnant rat uterine strips increased the mRNA and protein expressions of Gs protein but not the mRNA of β2- and β3-adrenoceptors. It also enhanced the expression of Gi-protein, but not the Gq protein. Nevertheless, the mRNA ratio of Gs to Gi protein experienced a significant decrease. Further, leptin reduced the transcription of BKCaα and BKCaβ channel subunits. In leptin-stimulated tissues, there was also an increase in the expression of leptin receptor and JAK-2. In conclusion, leptin decreases the ratio of Gs to Gi proteins and BKCaα and BKCaβ channel subunits suggesting hyperleptinemia is a likely factor inducing uterine relaxant dysfunction in obesity.

Dietary sulfur amino acid restriction in humans with overweight and obesity: a translational randomized controlled trial

BACKGROUND

Dietary sulfur amino acid restriction (SAAR) improves metabolic health in animals. In this study, we investigated the effect of dietary SAAR on body weight, body composition, resting metabolic rate, gene expression profiles in white adipose tissue (WAT), and an extensive blood biomarker profile in humans with overweight or obesity.

METHODS

N = 59 participants with overweight or obesity (73% women) were randomized stratified by sex to an 8-week plant-based dietary intervention low (~ 2 g/day, SAAR) or high (~ 5.6 g/day, control group) in sulfur amino acids. The diets were provided in full to the participants, and both investigators and participants were blinded to the intervention. Outcome analyses were performed using linear mixed model regression adjusted for baseline values of the outcome and sex.

RESULTS

SAAR led to a ~ 20% greater weight loss compared to controls (β 95% CI - 1.14 (- 2.04, - 0.25) kg, p = 0.013). Despite greater weight loss, resting metabolic rate remained similar between groups. Furthermore, SAAR decreased serum leptin, and increased ketone bodies compared to controls. In WAT, 20 genes were upregulated whereas 24 genes were downregulated (FDR < 5%) in the SAAR group compared to controls. Generally applicable gene set enrichment analyses revealed that processes associated with ribosomes were upregulated, whereas processes related to structural components were downregulated.

CONCLUSION

Our study shows that SAAR leads to greater weight loss, decreased leptin and increased ketone bodies compared to controls. Further research on SAAR is needed to investigate the therapeutic potential for metabolic conditions in humans.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04701346, registered Jan 8th 2021, https://www.

CLINICALTRIALS

gov/study/NCT04701346.

A crossover randomized controlled trial examining the effects of black seed (Nigella sativa) supplementation on IL-1β, IL-6 and leptin, and insulin parameters in overweight and obese women

BACKGROUND

Nigella sativa (NS) oil has been found to have advantageous benefits in the management of inflammation and obesity. This study investigated the effect of NS supplementation on blood mRNA expressions and serum levels of IL-1β, IL-6, leptin, and insulin concentrations in overweight/obese women.

METHODS

In a crossover design, participants were randomized to receive either NS supplements(2000 mg/day) or placebo for 2 durations(8 weeks). With between-subject and within-subject components and interactions, a repeated-measure ANOVA model was used considering the treatment, time, and the carryover effects. Cohen's d(d) was used to measure the magnitude of the effects.

RESULTS

Forty-six eligible participants were included. NS supplementation significantly reduced the mRNA expressions(d=-0.68, P = 0.03) and serum levels of IL-1β with medium-high effect sizes(d=-1.6, P < 0.001). Significant reductions with large effect sizes were observed in the gene expression and serum levels of IL-6(d=-1.8, d=-0.78, respectively; P < 0.01) and Leptin(d=-1.9, d=-0.89, respectively; P < 0.01, serum leptin P carryover < 0.001). Despite the meaningful carryover effect for serum leptin, results remained significant following the first intervention period analysis(P < 0.001). A significant but low effect size decrease in serum insulin was observed(d=-0.3, P = 0.02).

CONCLUSIONS

The clinical significance of present findings regarding improvements in obesity-related pro-inflammatory markers must be interpreted with caution due to some observed medium-low effect sizes.

TRIAL REGISTRATION

IRCT20180430039475N1 (Date:25/6/2018).

Adipocyte size, adipose tissue calories, and circulating adipokines, before and after diet-induced weight loss in humans

OBJECTIVE

Adipose tissue (AT) contains a bimodal population of large and small adipocytes. Changes in fat cell size (FCS) distribution and AT caloric density (kcal/g) with weight loss are unclear. We aimed to evaluate changes in FCS and AT calories in weight loss and determine associations with anthropometrics.

MATERIALS AND METHODS

Healthy adults (6 men/4 women; age 33 ± 11 years; BMI 35 ± 6 kg/m2) underwent DXA and subcutaneous abdominal/thigh fat biopsies, before and after 6 weeks of caloric restriction. AT calories (bomb calorimetry) and hormones (adiponectin, leptin, FGF21) were measured.

RESULTS

Abdominal large cell diameter (LCD; Δ = -13.2 μm, p = 0.01) and nadir (Δ = -7.3 μm, p = 0.03) decreased. In repeated measures correlations (rrm), abdominal and thigh LCD and nadir were associated with fat mass (FM) loss (rrm = 0.68; rrm = 0.63; rrm = 0.66; rrm = 0.62, p's < 0.05, respectively) and waist circumference decrease (rrm = 0.70; rrm = 0.60, p's ≤ 0.05). Small cell percentage did not change and was not associated with FM changes. Abdominal AT calories were unchanged with weight loss. Change in leptin was associated with change in abdominal LCD (rrm = 0.77, p = 0.01).

CONCLUSIONS

Caloric restriction reduces adipocyte LCD and nadir. These changes are associated with FM loss. Larger fat cells should be considered as phenotypic targets for weight loss.

CLINICAL TRIALS REGISTRATION

clinicaltrials.gov identifier: NCT00687115, May 29, 2008.

Effect of intermittent fasting on lipid biokinetics in obese and overweight patients with type 2 diabetes mellitus: prospective observational study

BACKGROUND

Intermittent fasting (IF) is a commonly used dietary practice that alternates between periods of unrestricted dietary consumption and abstinence from caloric intake. IF reduces caloric intake along with metabolic switch from utilization of glucose to fatty acids and ketones and resulting in reduction in adiposity and subsequently insulin resistance. Thus, it has been hypothesized that IF regimens can improve body composition in obese and overweight individuals.

AIM

To assess the effect of IF on lipid biokinetics in obese and overweight patients with type 2 diabetes (T2D).

PATIENTS AND METHODS

Thirty overweight or obese T2D patients were recruited from the diabetes outpatient clinics at the Specialized Medical Hospital, Mansoura University. Patients were subjected to time restricted fasting for 16 h (from dawn to sunset) during Ramadan. Anthropometric data were measured for participants before and 3 weeks after Ramadan fasting. Fasting plasma glucose (FPG), HbA1c, lipid profile, leptin, beta hydroxybutyrate (βHB) and high sensitive CRP levels were measured 1 week before and 3 weeks after Ramadan fasting.

RESULTS

30 diabetic patients were recruited with a mean age of 54.3 ± 7.2 years. 24 (80%) were females. Obesity was diagnosed in 27 cases (90%). The median diabetes duration was 10 years. The study showed a statistically significant decrease in post-fasting body weight (BW), Body mass index (BMI), waist circumference (WC) & hip circumference (HC). There was a statistically significant decrease of post-fasting low density lipoprotein (LDL-C), Total cholesterol (TC), and leptin. The study also showed a statistically significant increase of post-fasting high density lipoprotein (HDL-C) and βHB. No significant change was found in post-fasting levels of HbA1c, FPG, triglycerides (TG) or high sensitive CRP. Post-fasting leptin was positively correlated with post-fasting BW, BMI, WC, and HC. Post-fasting βHB was positively correlated with post-fasting TG, HbA1c, and LDL-C. Leptin levels change (pre vs post fasting) was positively correlated with the change in LDL-C levels.

CONCLUSION

IF reduced leptin and increased β-hydroxybutyrate levels. IF is an effective tool for losing weight and visceral fat and improving lipid profile in obese and overweight patients with T2D.