Dietary fatty acids and risk of Alzheimer's disease and related dementias: Observations from the Washington Heights-Hamilton Heights-Inwood Columbia Aging Project (WHICAP)

Introduction:

High dietary intake of long chain, polyunsaturated fatty acids is associated with lower Alzheimer’s disease (AD) risk.

Methods:

Washington Heights-Hamilton Heights-Inwood Columbia Aging Project is a multiethnic, prospective observational study of aging and dementia among elderly (≥ 65 years). Dietary intake was measured using a food frequency questionnaire. Dietary short-, medium-, and long-chain fatty acid intakes were categorized by number of carbons and double bonds. Consensus AD diagnoses were made. Associations between AD risk and dietary fatty acid and cholesterol intakes were estimated using multivariable Cox proportional hazards regression models.

Results:

Of 2612 multiethnic women (67%) and men (baseline age 76.3 [6.4] years), 380 developed AD over an average 4.5 years follow-up. Lower risk of AD was associated with increasing intakes of docosahexaenoic acid (DHA; hazard ratio [HR] = 0.73, 95% confidence interval [CI]: 0.57 to 0.95, P = 0.018) and eicosapentaenoic acid (EPA; HR = 0.74, 95% CI: 0.57 to 0.95, P = 0.021), and longer AD-free survival (P < 0.05).

Discussion:

Higher intake of DHA and EPA are protective for AD.

Characterization of CD19+ CD24hi CD38hi B cells in Chinese adult patients with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Human interleukin-10⁺ B cells (B10 cells) is one of regulatory B cells and is enriched in CD19⁺ CD24^hi CD38^hi B cells. A little is known about these cells in atopic dermatitis.

OBJECTIVE

To study CD19⁺ CD24^hi CD38^hi B cells and their clinical significance in Chinese adult patients with atopic dermatitis.

METHODS

Thirty-two adult patients with AD and nineteen healthy controls were enrolled. Peripheral blood mononuclear cells (PBMCs) were isolated and stained with fluorescein-conjugated monoclonal antibodies for CD19, CD24, CD27, CD38 and Annexin V. The stained PBMCs were analysed by flow cytometry. B10 cells were prepared by stimulating PBMCs with CpG, LPS and CD40L followed by restimulation with phorbol12-myristate 13-acetate (PMA) and ionomycin. Serum IL-10, B-cell-activating factor (BAFF) and a proliferation-inducing ligand (APRIL) levels were measured by using the ELISA. Apoptosis and proliferation of CD19⁺ CD24^hi CD38^hi B cells were measured by flow cytometry. 4/P-signal transducer and activator of transcription 3 (STAT3) and extracellular signal-regulated kinase 1/2 (Erk) phosphorylation were also studied.

RESULTS

The number of CD19⁺ CD24^hi CD38^hi B cells in patients with AD was similar to that in healthy controls. However, B10 cells were decreased in patients with AD. The proportion of B10 cells was negatively associated with blood basophil counts but not associated with disease activity. CD19⁺ CD24^hi CD38^hi B cells from AD patients were more susceptible to apoptosis upon stimulation with CpG, LPS and CD40L. B cells from AD patients showed lower STAT3 and Erk phosphorylation.

CONCLUSIONS

CD19⁺ CD24^hi CD38^hi B cells were unchanged in atopic dermatitis while B10 cells were decreased. The increased B-cell apoptosis, decreased STAT3 and Erk phosphorylation might contribute to these changes.

[Preliminary study of the relationship between novel coronavirus pneumonia and liver function damage: a multicenter study]

Objective: To analyze the clinical characteristics of cases of novel coronavirus pneumonia and a preliminary study to explore the relationship between different clinical classification and liver damage. Methods: Consecutively confirmed novel coronavirus infection cases admitted to seven designated hospitals during January 23, 2020 to February 8, 2020 were included. Clinical classification (mild, moderate, severe, and critical) was carried out according to the diagnosis and treatment program of novel coronavirus pneumonia (Trial Fifth Edition) issued by the National Health Commission. The research data were analyzed using SPSS19.0 statistical software. Quantitative data were expressed as median (interquartile range), and qualitative data were expressed as frequency and rate. Results: 32 confirmed cases that met the inclusion criteria were included. 28 cases were of mild or moderate type (87.50%), and four cases (12.50%) of severe or critical type. Four cases (12.5%) were combined with one underlying disease (bronchial asthma, coronary heart disease, malignant tumor, chronic kidney disease), and one case (3.13%) was simultaneously combined with high blood pressure and malignant tumor. The results of laboratory examination showed that the alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (ALB), and total bilirubin (TBil) for entire cohort were 26.98 (16.88 ~ 46.09) U/L and 24.75 (18.71 ~ 31.79) U/L, 39.00 (36.20 ~ 44.20) g/L and 16.40 (11.34 ~ 21.15) μmol/L, respectively. ALT, AST, ALB and TBil of the mild or moderate subgroups were 22.75 (16.31 ~ 37.25) U/L, 23.63 (18.71 ~ 26.50) U/L, 39.70 (36.50 ~ 46.10) g/L, and 15.95 (11.34 ~ 20.83) μmol/L, respectively. ALT, AST, ALB and TBil of the severe or critical subgroups were 60.25 (40.88 ~ 68.90) U/L, 37.00 (20.88 ~ 64.45) U/L, 35.75 (28.68 ~ 42.00) g/L, and 20.50 (11.28 ~ 25.00) μmol/L, respectively. Conclusion: The results of this multicenter retrospective study suggests that novel coronavirus pneumonia combined with liver damage is more likely to be caused by adverse drug reactions and systemic inflammation in severe patients receiving medical treatment. Therefore, liver function monitoring and evaluation should be strengthened during the treatment of such patients.

Akt2 Affects Periodontal Inflammation via Altering the M1/M2 Ratio

Periodontitis is a bacteria-driven inflammatory destructive disease that leads to attachment loss, bone resorption, and even tooth loss. Accumulating studies revealed that macrophages might play an nonnegligible role during the processes of periodontitis. However, the underlying mechanism remains largely unknown. In this study, we found novel Akt2/JNK1/2/c-Jun and Akt2/miR-155-5p/DET1/c-Jun signaling pathways that regulated the polarization of macrophages and altered periodontal inflammatory status. Through hematoxylin and eosin, immunostaining, and immunofluorescence staining of clinical specimens, a higher number of M1 phenotype macrophage infiltration was found in periodontitis than in normal controls. Flow cytometry and immunofluorescence showed that overexpression of Akt2 in RAW 264.7 cells induced M1 macrophage polarization and decreased M2 polarization, while knockdown of Akt2 exerted an opposite effect. Furthermore, overexpression of Akt2 activated the JNK pathway and then increased the release of proinflammatory mediators, while knockdown of Akt2 downregulated the above genes accordingly. Importantly, the macrophage polarization and the subsequent alteration of pathway molecules induced by overexpression of Akt2 could be rescued by Akt2 and JNK inhibitors. Moreover, JNK inhibition could facilitate M2 polarization of macrophages. In a mouse periodontitis model, the novel signaling pathway as well as clinical phenotype was further verified. Inhibition of Akt2 facilitated macrophage M2 polarization and rescued the bone loss due to periodontitis. Collectively, we identified novel Akt2/JNK1/2/c-Jun and Akt2/miR-155-5p/DET1/c-Jun signaling pathways that regulate macrophage polarization and highlight that Akt2 inhibition promotes M2 polarization of macrophages and can be a novel potential candidate in the treatment of periodontitis.

Prediction and Visualisation of Bony Impingement for Subject Specific Total Hip Arthroplasty

Bony impingement (BI) may contribute to restricted hip joint motion, and recurrent dislocation after total hip arthroplasty (THA), and therefore, should be avoided where possible. However, BI risk assessment is generally performed intra-operatively by surgeons, which is partially subjective and qualitative. Therefore, the aim of the study was to develop a method for identifying subject-specific BI, and subsequently, visualising BI area on native bone anatomy to highlight the amount of bone should be resected. Activity definitions and subject-specific bone geometries, constructed from CT scans, with planned implants were used as inputs for the method. For each activity, a conical clearance angle (CCA) was checked between femur and pelvis through simulation. Simultaneously, BI boundary and area were automatically calculated using ray intersection and region growing algorithm respectively. The potential use of the developed method was explained through a case study using an anonymised pre-THA patient data. Two pure (flexion, and extension) and two combined hip joint motions (internal and external rotation at flexion and extension respectively) were considered as activities. BI area were represented in two ways: (a) CCA specific where BI area for each activity with different CCAs was highlighted, (b) activity specific where BI area for all activities with a particular CCA was presented. Result showed that BI area between the femoral and pelvic parts was clearly identified so that the pre-operative surgical plan could be adjusted to minimise impingement. Therefore, this method could potentially be used to examine the effect of different preoperative plans and hip motion on BI, and to guide bony resection during THA surgery.

Sitagliptin improves cardiac function after myocardial infarction through activation of autophagy in streptozotocin-induced diabetic mice

OBJECTIVE

The aim of this study was to investigate the protective effect of sitagliptin on cardiac function in mice with diabetes and myocardial infarction (MI), and to explore its possible mechanism using the mouse models of diabetes and MI.

MATERIALS AND METHODS

The models of diabetes and MI were established using C57BL/6 mice. All mice were randomly divided into 5 groups, including the control sham (CS) group, the control MI (CMI) group, the diabetes sham (DS) group, diabetes + MI (DMI) group and the DMI + sitagliptin (DMI+SGL) group. After modeling, mice in the DMI+SGL group were intragastrically administrated with sitagliptin (10 mg/kg/day) for 21 d and the survival rate of mice was recorded. Before and 7, 14, 21 days after MI, the cardiac function of mice in each group was detected via ultrasound. 21 days after MI, the area of MI was measured via 2,3,5-triphenyl tetrazolium chloride (TTC). Meanwhile, the degree of fibrosis in the peripheral region of MI was determined via Masson staining. Moreover, myocardial autophagosomes of mice in each group were observed by transmission electron microscope (TEM). 7 days after MI, the expressions of autophagy-related proteins LC3II and P65 were detected via Western blotting. The expressions of myocardial inflammatory factors, interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) were detected via enzyme-linked immunosorbent assay (ELISA). In addition, the expression of nuclear factor-κB (NF-κB) was also detected via Western blotting.

RESULTS

Sitagliptin increased survival rate, improved cardiac function, reduced infarction area, alleviated myocardial fibrosis, enhanced autophagy in the peripheral region and inhibited inflammation in the peripheral region in mice with diabetes after MI.

CONCLUSIONS

Sitagliptin can improve cardiac function and reduce the mortality rate in diabetic rats after MI. The possible underlying mechanism may be related to the fact that sitagliptin activates autophagy and inhibits inflammatory response in diabetes after MI.

Hematopoietic and lymphatic cancers in patients with periodontitis: a systematic review and meta-analysis

Background

Numerous studies have explored the correlation of periodontal disease (PD) with risk of hematopoietic and lymphatic cancers, but the findings were inconsistent. Therefore, we did a meta-analysis to ascertain the correlation of PD with risk of incident hematopoietic and lymphatic cancers.

Material and Methods

The authors searched relevant studies in databases (PubMed, Web of Science, and MEDLINE). The summary relative risk (RR) along with 95% confidence interval (CI) was calculated by use of random or fixed effects models.

Results

Six studies were included in qualitative synthesis. The pooled analysis revealed that PD was significantly associated with an increased risk of hematopoietic and lymphatic cancers (RR = 1.17; 95% CI = 1.07–1.27; P = 0). Stratified analysis showed the association of PD with hematopoietic and lymphatic cancers remained significant in the never smokers (RR = 1.28; 95% CI = 1.07–1.54; P = 0.007), and in the American population (RR = 1.17; 95% CI = 1.05–1.30; P = 0.003), respectively.

Conclusions

Never smokers population and the American population with PD have a higher risk of developing hematopoietic and lymphatic cancers. PD might be considered as a risk factor for hematopoietic and lymphatic cancers.

Key words:Periodontal disease, hematopoietic and lymphatic cancer, meta-analysis, systematic review.

Characterization of peripheral blood mononuclear cells isolated using two kinds of leukocyte filters

OBJECTIVE

The objective of this study was to compare the activity and biological function of leukocytes isolated using apheresis platelet leukoreduction system chambers (LRSC), whole blood leukoreduction filters (LRF), and leukocytes in unfiltered peripheral whole blood (WB).

METHODS

Peripheral blood mononuclear cells (PBMCs) and granulocytes were obtained by density gradient centrifugation using recovery filters and WB. Flow cytometry was used to detect the activity, phenotype, and apoptosis ratio of each cell subtype.

RESULTS

The proportion of lymphocytes obtained from PBMCs was similar when using the two different filters as compared to traditional isolation; however, there were significant differences between the monocytes and granulocytes. The phenotypic frequency of lymphocytes was similar, but the apoptosis rate of lymphocytes from the two filters was slightly higher. Additionally, monocytes isolated via the three sources were able to be induced into dendritic cells expressing specific molecules; Granulocytes isolated from the LRF showed a lower purity and a higher level of apoptosis than granulocytes isolated from the WB.

CONCLUSION

Compared with WB, the PBMCs isolated from the filters used in our blood center had no statistical difference in their activity and biological function, but they did differ in the proportion and quantity of monocytes and granulocytes. Our results show that the two filters can be used as an alternative method to collect leukocytes, which solves the problem of an insufficient blood supply for clinical and basic science research. Thus, these filters have significant value beyond their practical use in clinics.

[Cone-beam CT analysis on the treatment efficacy in the vertically impacted maxillary central incisors]

Objective: To analyze the treatment efficacy in the vertically impacted maxillary central incisors using cone-beam CT (CBCT) and explore the treatment timing and the influence of orthodontic traction on the root development and alveolar bone height in the mixed dentition. Methods: Twenty-two patients with vertically impacted maxillary central incisor who were admitted to the Department of Orthodontics, Stomatological Hospital affiliated to Nanjing Medical University from December 2012 to December 2017 were selected [12 males and 10 females, (9.2±0.9) years]. Based on the dental age, patients were classified as early treatment group (teeth ranging from a third to two thirds of root formation, n=12) and late treatment group (teeth with nearly or fully complete root formation, n=10). The contralateral maxillary central incisor was used as the control. Three-dimensional reconstruction of CBCT before treatment, after treatment and one year after treatment was carried out to measure root length, tooth surface area, tooth volume, labial and lingual apical alveolar bone thickness, the loss of labial alveolar bone height and intraosseous root ratio. The clinical crown length was measured in the mouth. The difference values of the measurement variables between the impacted teeth and the control teeth were calculated and analyzed(measurement values of impacted teeth were subtracted from control values). Results: The values of root length difference beween the impacted teeth and the control teeth in the early and late treatment group were (1.58±1.56) mm and (2.57±1.00) mm, respectively after the treatment and the values were significantly less than those corresponding values before treatment [(3.47±1.40) and (3.36±0.79) mm] (P<0.05). After the treatment, the values of the surface area and volume difference between the impacted teeth and the control teeth in the early treatment group [(0±34) mm(2) and (-10±44) mm(3)] were significantly less than those corresponding values before treatment [(38±31) mm(2) and (55±70) mm(3)] (P<0.05). The value differences of any measurement variables between the early and late treatment group were not significantly different after the treatment (P>0.05). The root length and intraosseous root ratio of the impacted teeth after the treatment in the early and late treatment group were significantly less than those of the control teeth after the treatment (P<0.05). The clinical crown length, the loss of labial alveolar bone height of the impacted teeth after the treatment were significantly larger than those of the control teeth after the treatment (P<0.05). Conclusions: Orthodontic traction promoted the root growth and development of the vertically impacted maxillary central incisors. However, the root length and alveolar bone height still cannot reach the normal level after treatment. Treatment timing had no effect on root development and alveolar bone height of vertically impacted maxillary central incisors in mixed dentition.

Excessive daytime sleepiness with snoring or witnessed apnea is associated with handgrip strength: a population-based study

BACKGROUND

Sarcopenia is emerging as an important public health problem, and evidences have determined that poor sleep is associated with muscle strength, but the potential effects of excessive daytime sleepiness (EDS), snoring and witnessed apnea on handgrip strength have not been evaluated.

AIM

We aimed to examine the association between EDS, snoring, witnessed apnea and muscle strength in an adult population.

DESIGN

Cross-sectional study.

METHODS

This cross-sectional study comprised 19 434 adults. Handgrip strength was measured using a handheld digital dynamometer. EDS was assessed by Epworth Sleepiness Scale, snoring and witnessed apnea during sleep were reported through simple yes/no questions. Analysis of covariance was carried out to determine the association between EDS with snoring or witnessed apnea and muscle strength.

RESULTS

The means (95% confidence interval) for average handgrip strength/body weight (kg/kg) across symptoms categories were 0.396 (0.333-0.472), 0.393 (0.330-0.467), 0.396 (0.333-0.471) and 0.386 (0.325-0.460) (P < 0.0001), respectively. Similar results were observed with maximal handgrip strength/body weight (kg/kg).

CONCLUSIONS

Self-reported EDS accompanied with snoring or apnea is associated with lowest handgrip strength, independently of confounding factors. Whether improvement of EDS, snoring and apnea, can ameliorate age-associated decline in muscle strength warrants further studies.

Cerebral Damage after Carbon Monoxide Poisoning: A Longitudinal Diffusional Kurtosis Imaging Study

BACKGROUND AND PURPOSE

Previous DTI cross-sectional studies have showed the cerebral damage feature was different in the three clinical stages after carbon monoxide poisoning. Diffusional kurtosis imaging (DKI) is an advanced diffusion imaging model and considered to better provide microstructural contrast in comparison with DTI parameters. The primary aim of this study was to assess microstructural changes in gray and white matter with diffusional kurtosis imaging in the acute, delayed neuropsychiatric, and chronic phases after acute carbon monoxide (CO) poisoning. The secondary aim was to relate diffusional kurtosis imaging measures to neuropsychiatric outcomes of acute carbon monoxide poisoning.

MATERIALS AND METHODS

In all, 17 patients with acute carbon monoxide poisoning and 30 sex- and age-matched healthy volunteers were enrolled in the study. Patients were scanned within 1 week, 3-8 weeks, and 6 months after acute carbon monoxide poisoning. Diffusional kurtosis imaging metrics including mean kurtosis, mean diffusivity, fractional anisotropy, and kurtosis fractional anisotropy were measured in 11 ROIs and then further correlated with neuropsychiatric scores.

RESULTS

In WM, mean kurtosis tended to increase from the acute-to-delayed neuropsychiatric phases and then decrease in the chronic phase, while in GM mean kurtosis showed a constant decline. Contrary to mean kurtosis, mean diffusivity first decreased then tended to increase in WM, while in GM, from the acute to chronic phases, mean diffusivity showed a constant increase. In both WM and GM, the fractional anisotropy and kurtosis fractional anisotropy values progressively declined with time. Kurtosis fractional anisotropy showed the best diagnostic efficiency with an area under the curve of 0.812 (P = .000). Along with neuropsychiatric scores, kurtosis fractional anisotropy of the centrum semiovale and Digit Span Backward were most relevant (r = 0.476, P = .000).

CONCLUSIONS

Longitudinally, microstructural changes were inconsistent in WM and GM with time after acute carbon monoxide poisoning. Diffusional kurtosis imaging metrics provided important complementary information to quantify the damage to cognitive impairment.

Adalimumab medium-term dosing strategy in moderate-to-severe hidradenitis suppurativa: integrated results from the phase III randomized placebo-controlled PIONEER trials

Background

Weekly adalimumab (Humira^®) is approved for the treatment of hidradenitis suppurativa (HS) based on the 12‐week placebo‐controlled periods of the two phase III PIONEER trials.

Objectives

Using PIONEER integrated trial results, we aimed to evaluate the optimal medium‐term adalimumab maintenance dosing strategy for moderate‐to‐severe HS.

Methods

Each trial had two double‐blind periods; 12‐week Period A and 24‐week Period B. Patients randomized to adalimumab 40 mg every week (ADAew) (Period A), were rerandomized in Period B to ADAew (ADAew/ew), ADA every other week (ADAew/eow), or placebo (ADAew/pbo). Placebo‐randomized patients were reassigned in Period B to ADAew (PIONEER I) or placebo (PIONEER II). The primary outcome was HS Clinical Response (HiSCR). Patients who lost response during Period B were discontinued from the study and offered an option to enter the open‐label extension (OLE) to receive ADAew. Results are reported across the two study periods, and data were combined from the two study periods and the OLE.

Results

For week‐12 HiSCR achievers, the HiSCR week‐36 rate was 48·1% (ADAew/ew) vs. 46·2% (ADAew/eow) and 32·1% (ADAew/pbo). Combining (post hoc) these patients with week‐12 partial responders further differentiated outcomes in Period B (ADAew/ew 55·7% vs. ADAew/eow 40·0% and ADAew/pbo 30·1%). Period‐B adverse‐event rates were ADAew/ew 59·6% vs. ADAew/eow 57·4% and ADAew/pbo 65·0%. One patient (ADAew/ew) reported a serious infection.

Conclusions

Weekly adalimumab treatment, effective throughout 36 weeks, was the optimal maintenance medium‐term dosing regimen for this population. At least partial response after 12 weeks with continued weekly dosing had better outcomes than dose reduction or interruption. Patients who do not show at least a partial response to weekly adalimumab by week 12 are unlikely to benefit from continued therapy. No new safety risks were identified.

What's already known about this topic?

Hidradenitis suppurativa (HS) is a chronic inflammatory disease, commonly misinterpreted as an infection and treated with long‐term antibiotic regimens or surgical incisions.

Based on the chronicity of HS and the lack of evidence for efficacious and safe long‐term HS treatments, it is important to evaluate medium‐ to long‐term therapies for HS.

Weekly adalimumab (Humira^®) is approved for the treatment of moderate‐to‐severe HS based on the two phase III PIONEER trials.

What does this study add?

This study pooled data from the two PIONEER trials, providing a more robust assessment of outcomes.

After at least partial treatment success with weekly adalimumab short‐term therapy (12 weeks), continuing weekly dosing during the subsequent 24 weeks had better outcomes than dose reduction or treatment interruption.

Patients who do not show at least a partial response to weekly adalimumab by week 12 are unlikely to benefit from continued therapy.

Linked Comment: https://doi.org/10.1111/bjd.18437.

https://www.bjdonline.com/article/adalimumab-medium-term-dosing-strategy-in-moderate-to-severe-hidradenitis-suppurativa-integrated-results-from-the-phase-iii-randomized-placebo-controlled-pioneer-t/

[Retrospective analysis of 4 rare cases of temporomandibular joint disc ossification]

Objective: To summarize the clinical manifestation and treatment of temporomandibular joint (TMJ) disc ossification, providing reference for clinical diagnosis and treatment of TMJ disc ossification. Methods: From January 2006 to January 2018, 4 patients with TMJ disc ossification (2 males and 2 females, aged 20-55 years with an average age of 35.5 years) which were admitted to the Department of Oral and Maxillofacial Surgery, Shenzhen Second People's Hospital were analyzed retrospectively. Ossification of TMJ disc was found in 4 cases during TMJ surgery. Two cases underwent partial ossification resection plus disc reduction and anchorage, and two cases underwent discectomy plus temporalis myofascial flap replacement. The causes, clinical manifestations and surgical effects of TMJ disc ossification were analyzed by comparing the maximal interincisal opening, visual analogue scale (VAS) score and MRI imaging indexes before and after operation. Results: The history of anterior disc displacement of TMJ in 4 patients was long (average 11.5 years). In clinic, TMJ disc ossification was characterized by TMJ pain and limitation of mouth opening. The maximal interincisal opening was (32.1±6.1) mm and the VAS score was (7.3±0.4) before operation. MRI showed that the displaced discs of the affected sides were displaced and the condyle bones were worn. During the operation, ossification of TMJ discs was found yellow and hard, and the original elasticity was lost. Pathologic findings showed that the TMJ disc cartilage were ossified to osteoid tissue. Under the microscope, bone cells scattered around the bone cells and red trabecular bone were seen, and there were bone trabecula formed. In a follow-up of one year, TMJ pain was significantly decreased [VAS: (1.7±0.2)], and the maximal interincisal opening was (38.5±2.2) mm. MRI showed that the TMJ disc returned to normal position, and the sign of repairing and reconstruction of condyle bone could be found. Conclusions: Long term displacement of TMJ disc may cause ossification with pain and limitation of interincisal opening. According to the degree and extent of ossification, partial ossification plus disc reduction and anchorage or discectomy plus temporalis myofascial flap replacement is feasible, and the clinical effects are satisfactory.

Comparison of microRNAs in adipose and muscle tissue from seven indigenous Chinese breeds and Yorkshire pigs

Elucidation of the pig microRNAome is essential for interpreting functional elements of the genome and understanding the genetic architecture of complex traits. Here, we extracted small RNAs from skeletal muscle and adipose tissue, and we compared their expression levels between one Western breed (Yorkshire) and seven indigenous Chinese breeds. We detected the expression of 172 known porcine microRNAs (miRNAs) and 181 novel miRNAs. Differential expression analysis found 92 and 12 differentially expressed miRNAs in adipose and muscle tissue respectively. We found that different Chinese breeds shared common directional miRNA expression changes compared to Yorkshire pigs. Some miRNAs differentially expressed across multiple Chinese breeds, including ssc-miR-129-5p, ssc-miR-30 and ssc-miR-150, are involved in adipose tissue function. Functional enrichment analysis revealed that the target genes of the differentially expressed miRNAs are associated mainly with signaling pathways rather than metabolic and biosynthetic processes. The miRNA-target gene and miRNA-phenotypic traits networks identified many hub miRNAs that regulate a large number of target genes or phenotypic traits. Specifically, we found that intramuscular fat content is regulated by the greatest number of miRNAs in muscle tissue. This study provides valuable new candidate miRNAs that will aid in the improvement of meat quality and production.

Autonomic Activity in Overweight-Obese Children During the Morning Transition in Cardiac Circadian Regulation (P21-065-19)

Objectives

Regulation of the autonomic nervous system is disturbed in obese children and adults. This dysregulation—which includes sympathetic nervous system (SNS) over activity and disruption of cardiac circadian rhythms—is of interest because of the negative impact of these effects on cognition, regulation of energy homeostasis, cardiovascular health, and metabolic functions. The present study evaluated heart rate (HR) measures during the first hours following awakening from sleep when circadian cardiac control transitions from an emphasis on parasympathetic nervous system activity (PNS) during sleep to an emphasis on SNS activity during wakefulness.

Methods

Resting HR recordings (5 min) were obtained from healthy normal weight (NW: BMI < 85th %ile; n = 47; 25 boys) and overweight-obese (OB: BMI > 95th %ile; n = 48; 24 boys) 10 yr olds enrolled in the ACNC's Brain Food study. The first of two recording sessions (T1) took place 2 hrs after awakening (1 hr after a standardized breakfast), and the second (T2) 1 hr later. Recordings were processed for measures of sympathetic [low frequency (LF)] and parasympathetic [high frequency (HF); vagal tone (VT); root mean square of intervals between adjacent heart beats (RMSSD)] activities.

Results

Separate ANOVAs (recording session by group by sex) were conducted for each measure. Previous reports of higher HR in girls than boys and in OB than NW groups were confirmed (both P ≤ 0.001) HR slowed significantly from T1 to T2 for OB (P = 0.021), but not NW. These effects were associated with T1 to T2 increases in SNS LF activity for both groups (both P ≤ 0.003), but significant increases in PNS measures (HF, RMSSD, VT; all P < 0.05) for only OB children. Increases in PNS activity across recording sessions for OB children attenuated group HR differences during T2 (T1: OB > NW, P = 0.008; T2: OB > NW, P = .051). Gender differences were consistent with faster HR in girls which was maintained across groups and recording sessions.

Conclusions

The results are the first to show that autonomic dysregulation in obese children modulates the shift in SNS-PNS balance characteristic of the transition from sleep to waking. These findings may inform the development of new early intervention strategies to attenuate obesity that consider the role played by circadian rhythms.

Funding Sources

Funded by USDA-ARS Project 6026-51000-010-05S.