Hypothalamic anorexigenic signaling pathways (leptin, amylin, and proopiomelanocortin) are semaglutide (GLP-1 analog) targets in obesity control in mice

Obesity, White Adipose Tissue, and Adipokines Signaling in Male Reproduction

Currently, obesity is a global pandemic characterized by systemic metabolic complications that negatively impact several organs, including white adipose tissue (WAT) and the tissues of the male reproductive system. Since the discovery of leptin in 1994, WAT has been recognized as a dynamic endocrine organ for secreting a series of molecules with hormonal functions, collectively called adipokines. The link between obesity, WAT, adipokines, and the male reproductive system is direct and little explored. With changes in nutritional status, WAT undergoes morphofunctional changes, and the secretion of adipokines is altered, negatively impacting reproductive mechanisms, including steroidogenesis and spermatogenesis. In this review, we address in an updated way the structural and functional characteristics of WAT as well as the link between obesity and changes in the signaling pathways of the adipokines leptin, adiponectin, resistin, visfatin, apelin, chemerin, omentin-1, vaspin, and asprosin in male reproduction. Understanding the relationship between obesity, these adipokines, and reproductive dysfunction can contribute to new strategies for the treatment of subfertility and male infertility.

Anorexigenic and anti-inflammatory signaling pathways of semaglutide via the microbiota-gut--brain axis in obese mice

Our study focused on a mouse model of obesity induced by a high-fat diet (HFD). We administered Semaglutide intraperitoneally (Ozempic ®-0.05 mg/Kg-translational dose) every seven days for six weeks. HFD-fed mice had higher blood glucose, lipid profile, and insulin resistance. Moreover, mice fed HFD showed high gut levels of TLR4, NF-kB, TNF-α, IL-1β, and nitrotyrosine and low levels of occludin, indicating intestinal inflammation and permeability, culminating in higher serum levels of IL-1β and LPS. Treatment with semaglutide counteracted the dyslipidemia and insulin resistance, reducing gut and serum inflammatory markers. Structural changes in gut microbiome were determined by 16S rRNA sequencing. Semaglutide reduced the relative abundance of Firmicutes and augmented that of Bacteroidetes. Meanwhile, semaglutide dramatically changed the overall composition and promoted the growth of acetate-producing bacteria (Bacteroides acidifaciens and Blautia coccoides), increasing hypothalamic acetate levels. Semaglutide intervention increased the number of hypothalamic GLP-1R+ neurons that mediate endogenous action on feeding and energy. In addition, semaglutide treatment reversed the hypothalamic neuroinflammation HDF-induced decreasing TLR4/MyD88/NF-κB signaling and JNK and AMPK levels, improving the hypothalamic insulin resistance. Also, semaglutide modulated the intestinal microbiota, promoting the growth of acetate-producing bacteria, inducing high levels of hypothalamic acetate, and increasing GPR43+ /POMC+ neurons. In the ARC, acetate activated the GPR43 and its downstream PI3K-Akt pathway, which activates POMC neurons by repressing the FoxO-1. Thus, among the multifactorial effectors of hypothalamic energy homeostasis, possibly higher levels of acetate derived from the intestinal microbiota contribute to reducing food intake.

Spotlight on the Mechanism of Action of Semaglutide

Initially intended to control blood glucose levels in patients with type 2 diabetes, semaglutide, a potent glucagon-like peptide 1 analogue, has been established as an effective weight loss treatment by controlling appetite. Integrating the latest clinical trials, semaglutide in patients with or without diabetes presents significant therapeutic efficacy in ameliorating cardiometabolic risk factors and physical functioning, independent of body weight reduction. Semaglutide may modulate adipose tissue browning, which enhances human metabolism and exhibits possible benefits in skeletal muscle degeneration, accelerated by obesity and ageing. This may be attributed to anti-inflammatory, mitochondrial biogenesis, antioxidant and autophagy-regulating effects. However, most of the supporting evidence on the mechanistic actions of semaglutide is preclinical, demonstrated in rodents and not actually confirmed in humans, therefore warranting caution in the interpretation. This article aims to explore potential innovative molecular mechanisms of semaglutide action in restoring the balance of several interlinking aspects of metabolism, pointing to distinct functions in inflammation and oxidative stress in insulin-sensitive musculoskeletal and adipose tissues. Moreover, possible applications in protection from infections and anti-aging properties are discussed. Semaglutide enhancement of the core molecular mechanisms involved in the progress of obesity and diabetes, although mostly preclinical, may provide a framework for future research applications in human diseases overall.

Semaglutide as a potential treatment for obesity in Smith-Kingsmore syndrome (SKS) patients: A mosaic mutation case report

We present for the first-time efficacy and tolerability of GLP-1-RA (Semaglutide) in Smith-Kingsmore syndrome (SKS). SKS is a rare genetic disorder characterized by intellectual disability, macrocephaly, seizures and distinctive facial features due to MTOR gene mutation. We present a 22-year-old woman with mosaic SKS and severe obesity (Body Mass Index ≥40 kg/m²), treated with semaglutide. She achieved a 9 kg (7.44%) weight loss over 12 months without adverse effects.This case highlights semaglutide's potential in managing obesity in SKS patients, emphasizing the need for further research in this rare genetic disorder.

Cotadutide (GLP-1/Glucagon dual receptor agonist) modulates hypothalamic orexigenic and anorexigenic neuropeptides in obese mice

The hypothalamic neuropeptides linked to appetite and satiety were investigated in obese mice treated with cotadutide (a dual receptor agonist of glucagon-like peptide 1 (GLP-1R)/Glucagon (GCGR)). Twelve-week-old male C57BL/6 mice were fed a control diet (C group, n = 20) or a high-fat diet (HF group, n = 20) for ten weeks. Each group was further divided, adding cotadutide treatment and forming groups C, CC, HF, and HFC for four additional weeks. The hypothalamic arcuate neurons were labeled by immunofluorescence, and protein expressions (Western blotting) for neuropeptide Y (NPY), proopiomelanocortin (POMC), agouti-related protein (AgRP), and cocaine- and amphetamine-regulated transcript (CART). Cotadutide enhanced POMC and CART neuropeptides and depressed NPY and AGRP neuropeptides. In addition, gene expressions (RT-qPCR) determined that Lepr (leptin receptor) and Calcr (calcitonin receptor) were diminished in HF compared to C but enhanced in CC compared to C and HFC compared to HF. Besides, Socs3 (suppressor of cytokine signaling 3) was decreased in HFC compared to HF, while Sst (somatostatin) was higher in HFC compared to HF; Tac1 (tachykinin 1) and Mc4r (melanocortin-4-receptor) were lower in HF compared to C but increased in HFC compared to HF. Also, Glp1r and Gcgr were higher in HFC compared to HF. In conclusion, the findings are compelling, demonstrating the effects of cotadutide on hypothalamic neuropeptides and hormone receptors of obese mice. Cotadutide modulates energy balance through the gut-brain axis and its associated signaling pathways. The study provides insights into the mechanisms underlying cotadutide's anti-obesity effects and its possible implications for obesity treatment.

Associations of Adipocytokines with The Development of Cardiovascular Events in Young People

The research was aimed to study the associations of adipocytokines with the risk of cardiovascular events and to determine the threshold values of adipocytes for the prognosis of cardiovascular events in a young population.

MATERIALS AND METHODS

The study is an epidemiological cohort study. The analysis included 1240 people aged 25-44 years. The endpoint was combined and included: death from cardiovascular disease, myocardial infarction, probable myocardial infarction, acute cerebrovascular accident, hospitalization for cardiovascular disease, and revascularization. Adipocytokines were determined with a MILLIPLEX panel.

RESULTS

In the examined population, 1.7% of cases of cardiovascular events were detected during cohort observation, of which 28.6% were fatal events. In men, cardiovascular endpoints were recorded 4.3 times more often than in women (17 (81%) vs. 4 (19%), p = 0.003). In individuals with cardiovascular events, arterial hypertension (2.6 times), diabetes mellitus (8.6 times), and overweight/obesity (1.5 times) were more often recorded compared to individuals without cardiovascular events. For tumor necrosis factor-alpha (TNFa), the threshold value was 2.5 pg/mL, with sensitivity assessment (Se) at 85.7% and specificity (Sp) at 83.3%. For amylin, the threshold value was 10.5 pg/mL, with Se at 73.7% and Sp at 67.0%. For pancreatic polypeptide (PP), the threshold value was 43.7 pg/mL, with Se at 85.7% and Sp at 56.7%.

CONCLUSION

A method for assessing the risk of cardiovascular events in young people includes determining the levels of amylin, PP, and TNFa in blood serum. The cut-off points for predicting cardiovascular events were levels of amylin above 10.5 pg/mL, PP above 43.7 pg/mL, or a decrease in TNFa below 3.8 pg/mL.

Antismoking agents do not contribute synergistically to semaglutide's ability to reduce alcohol intake in rats

Preclinical studies have identified glucagon-like peptide-1 receptor (GLP-1R) agonists, and the antismoking agents varenicline and bupropion as tentative agents for treatment of alcohol use disorder (AUD). Combining different medications is a recent approach that has gained attention regarding heterogenous and difficult-to-treat diseases, like AUD. Successfully, this approach has been tested for the combination of varenicline and bupropion as it prevents relapse to alcohol drinking in rats. However, studies assessing the effects of the combination of semaglutide, an FDA-approved GLP-1R agonist for diabetes type II, and varenicline or bupropion to reduce alcohol intake in male and female rats remains to be conducted. Another approach to influence treatment outcome is to combine a medication with feeding interventions like high fat diet (HFD). While HFD reduces alcohol intake, the ability of the combination of HFD and semaglutide to alter alcohol drinking is unknown and thus the subject for a pilot study. Therefore, three intermittent alcohol drinking experiments were conducted to elucidate the effectiveness of these treatment combinations. We show that semaglutide, bupropion or HFD reduces alcohol intake in male as well as female rats. While various studies reveal beneficial effects of combinatorial pharmacotherapies for the treatment of AUD, we herein do not report any additive effects on alcohol intake by adding either varenicline or bupropion to semaglutide treatment. Neither does HFD exposure alter the ability of semaglutide to reduce alcohol intake. Although no additive effects by the combinatorial treatments are found, these findings collectively provide insight into possible monotherapeutical treatments for AUD.

Molecular Mechanisms of Western Diet-Induced Obesity and Obesity-Related Carcinogenesis-A Narrative Review

The present study aims to provide a narrative review of the molecular mechanisms of Western diet-induced obesity and obesity-related carcinogenesis. A literature search of the Cochrane Library, Embase and Pubmed databases, Google Scholar and the grey literature was conducted. Most of the molecular mechanisms that induce obesity are also involved in the twelve Hallmarks of Cancer, with the fundamental process being the consumption of a highly processed, energy-dense diet and the deposition of fat in white adipose tissue and the liver. The generation of crown-like structures, with macrophages surrounding senescent or necrotic adipocytes or hepatocytes, leads to a perpetual state of chronic inflammation, oxidative stress, hyperinsulinaemia, aromatase activity, activation of oncogenic pathways and loss of normal homeostasis. Metabolic reprogramming, epithelial mesenchymal transition, HIF-1α signalling, angiogenesis and loss of normal host immune-surveillance are particularly important. Obesity-associated carcinogenesis is closely related to metabolic syndrome, hypoxia, visceral adipose tissue dysfunction, oestrogen synthesis and detrimental cytokine, adipokine and exosomal miRNA release. This is particularly important in the pathogenesis of oestrogen-sensitive cancers, including breast, endometrial, ovarian and thyroid cancer, but also 'non-hormonal' obesity-associated cancers such as cardio-oesophageal, colorectal, renal, pancreatic, gallbladder and hepatocellular adenocarcinoma. Effective weight loss interventions may improve the future incidence of overall and obesity-associated cancer.

Obesity and Type 2 Diabetes: Adiposopathy as a Triggering Factor and Therapeutic Options

Obesity and type 2 diabetes (T2DM) are major public health concerns associated with serious morbidity and increased mortality. Both obesity and T2DM are strongly associated with adiposopathy, a term that describes the pathophysiological changes of the adipose tissue. In this review, we have highlighted adipose tissue dysfunction as a major factor in the etiology of these conditions since it promotes chronic inflammation, dysregulated glucose homeostasis, and impaired adipogenesis, leading to the accumulation of ectopic fat and insulin resistance. This dysfunctional state can be effectively ameliorated by the loss of at least 15% of body weight, that is correlated with better glycemic control, decreased likelihood of cardiometabolic disease, and an improvement in overall quality of life. Weight loss can be achieved through lifestyle modifications (healthy diet, regular physical activity) and pharmacotherapy. In this review, we summarized different effective management strategies to address weight loss, such as bariatric surgery and several classes of drugs, namely metformin, GLP-1 receptor agonists, amylin analogs, and SGLT2 inhibitors. These drugs act by targeting various mechanisms involved in the pathophysiology of obesity and T2DM, and they have been shown to induce significant weight loss and improve glycemic control in obese individuals with T2DM.