Depletion of JunB increases adipocyte thermogenic capacity and ameliorates diet-induced insulin resistance.

The coexistence of brown adipocytes with low and high thermogenic activity is a fundamental feature of brown adipose tissue heterogeneity and plasticity. However, the mechanisms that govern thermogenic adipocyte heterogeneity and its significance in obesity and metabolic disease remain poorly understood. Here we show that in male mice, a population of transcription factor jun-B (JunB)-enriched (JunB+) adipocytes within the brown adipose tissue exhibits lower thermogenic capacity compared to high-thermogenic adipocytes. The JunB+ adipocyte population expands in obesity. Depletion of JunB in adipocytes increases the fraction of adipocytes exhibiting high thermogenic capacity, leading to enhanced basal and cold-induced energy expenditure and protection against diet-induced obesity and insulin resistance. Mechanistically, JunB antagonizes the stimulatory effects of PPARγ coactivator-1α on high-thermogenic adipocyte formation by directly binding to the promoter of oestrogen-related receptor alpha, a PPARγ coactivator-1α downstream effector. Taken together, our study uncovers that JunB shapes thermogenic adipocyte heterogeneity, serving a critical role in maintaining systemic metabolic health.

Gender parity in high impact neurology journals.

Background: Although female representation has been growing among physicians, women continue to be underrepresented in neurology, particularly regarding academic research in authorship and leadership. Analyzing recent trends in high-impact neurology journals highlights the underrepresentation of women and helps explore barriers to female representation in academic neurology. Methods and results: Journal Citation Reports (JCR) for 2021 was used to screen neurology journals for selection. The first 15 journals with the highest impact factors (JIF) were included. 15,404 total articles in neurology were examined for gender distribution of editorial staff and authorship with the highest total citations from January 1st, 2018 to October 31st, 2021. Gender was classified using biographical information from public and personal media sources. Genderize.io was used in cases of ambiguity, predicting gender at probability of ≥95%. Our data demonstrated that these journals only had 13% female editor-in-chiefs and 35% female editorial staff. The data further demonstrated that females accounted for 39% of first authors and 26% for last authors. During the four years examined males continued to account for the vast majority of both first and last authors for publications accepted and journal editorial staff members. Conclusion: Women are significantly under-represented in the field of neurological research in leadership positions as editor-in-chiefs, editorial board members as well as first or senior authors in top neurology medical journals. With continued underrepresentation of women occupying leading publishing roles, parity with men is still a work in progress. Additional work is needed to identify and address barriers to academic advancement for women physicians in academic neurology.

Cerebral venous sinus thrombosis associated with SRA-negative heparin-induced thrombocytopenia: case report.

BACKGROUND: There are very few documented reports in literature of cerebral venous sinus thrombosis (CVST) caused by immune-mediated heparin-induced thrombocytopenia (HIT). Further, there are very few reports of false negative serotonin release assays (SRAs) when testing for immune-mediated HIT. CASE PRESENTATION: We present a case of a 60- year-old male with recent unfractionated heparin administration for venous thromboembolism prophylaxis, an elevated 4T score of 5 and acute CVST in which immune-mediated HIT was suspected. The enzyme-linked immunosorbent assay (ELISA) screening assay was positive for PF4 antibodies and subsequent reflexive SRA testing was negative. However, given the clinical picture, a false-negative SRA was suspected (and eventually confirmed), prompting use of the alternative PF4-dependent p-selectin expression assay (PEA) which was confirmed to be positive. The patient was successfully managed with a bivalirudin infusion and eventually transitioned to apixaban. CONCLUSION: It is uncommon for immune-mediated HIT with thrombosis to manifest as CVST. Similarly, false-negative SRA is uncommon in immune-mediated HIT. Take-away lessons from our case report include considering HIT in CVST patients with an elevated 4T score and considering the entire clinical picture and degree of suspicion for HIT when interpreting negative HIT testing results. The PEA, in conjunction with the 4Ts score, may be considered as an alternate diagnostic assay for HIT.

Unusual presentation of idiopathic Bell's palsy with involvement of the oculomotor nerve.

Our patient presented with symptoms consistent with Bell's palsy. The involved cranial nerves were the facial and oculomotor nerves. She had preceding upper respiratory tract infection symptoms. She had no risk factors or significant illnesses, and no other causes were found. Although there are reported cases of multiple cranial nerves affected in Bell's palsy, our review of literature revealed no prior cases of involvement of the parasympathetic oculomotor fibres in Bell's palsy.

Cutaneous hydrophilic polymer emboli following endovascular repair of an abdominal aortic aneurysm: a case and review of literature.

Hydrophilic polymer embolism (HPE) is a rare iatrogenic complication of the use of polymer-coated intravascular devices, which may affect several organ systems including the skin. Herein, we present a patient who developed a cutaneous eruption with associated neurologic manifestations secondary to localized HPE. This is a potentially underdiagnosed, life-threatening complication and physicians should consider HPE when evaluating skin eruptions in patients who have undergone endovascular procedures.

Sex difference in lipid levels in first-diagnosed drug-naïve depression patients: A case-control and 12-weeks follow-up study.

AIM: Patients with depression have a high prevalence of developing dyslipidemia. In this study, we aim to investigate the difference of serum lipids, including total cholesterol (TCH), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), between the depressed patients and healthy controls. Sex differences in lipids and their psychological correlations were also included. METHODS: The study included 56 healthy controls (males/females = 26/30) and 110 first-diagnosed drug-naïve outpatients (males/females = 35/75). A total of 42 patients (males/females = 14/28) were followed for 3 months. RESULTS: A significant difference was found in TCH and LDL-C among healthy control and patients. Interestingly, female patients with first-diagnosed, drug-naïve depression had lower atherogenic indices than male patients. After 3 months of antidepressants therapy, female patients exhibited detrimental changes in serum lipids, namely increased TG and atherogenic index. Moreover, correlation analysis showed significant correlations between changes of depression inventory (HAMD and BDI) score and serum lipids (TCH, HDL-C) in depressed patients. CONCLUSION: We found that dyslipidemia was more common in female patients with depression during therapy with antidepressants. Moreover, the altered serum lipids and atherogenic index might be a hallmark of female patients. Further investigation of sex differences in lipid metabolism of depression is warranted.

Cerebral glucose metabolism in bipolar disorder: A voxel-based meta-analysis of positron emission tomography studies.

BACKGROUND: Previous positron emission tomography studies have reported the changes of cerebral glucose metabolism in bipolar disorder. However, the findings across studies remain controversial, containing differing results. METHODS: A systematic literature search of the PubMed, Embase, Cochrane Library, and Web of Science databases was conducted. We conducted a voxel-wide meta-analysis of cerebral glucose metabolism studies, using the seed-based mapping approach, in patients with bipolar disorder (BD). RESULTS: We identified 7 studies suitable for inclusion, which included a total of 126 individuals with BD and 160 healthy controls. The most consistent and robust findings were an increase in cerebral glucose metabolism in the right precentral gyrus and a decrease in the left superior temporal gyrus, left middle temporal gyrus, and cerebellum. Additionally, the sex distribution and illness duration had significant moderating effects on cerebral glucose metabolism alterations. CONCLUSIONS: Cerebral glucose metabolism alterations in these brain regions are likely to reflect the disease-related functional abnormalities such as emotion and cognition. These findings contribute to a better understanding of the neurobiological underpinnings of bipolar disorder. LIMITATIONS: This study was done at a study level and cannot be addressed at the patient level. Subgroup analysis of BD I and BD II is not possible due to limited literature data.

Adiponectin restrains ILC2 activation by AMPK-mediated feedback inhibition of IL-33 signaling.

ILC2s are present in adipose tissue and play a critical role in regulating adipose thermogenesis. However, the mechanisms underlying the activation of adipose-resident ILC2s remain poorly defined. Here, we show that IL-33, a potent ILC2 activator, stimulates phosphorylation of AMPK at Thr172 via TAK1 in primary ILC2s, which provides a feedback mechanism to inhibit IL-33-induced NF-κB activation and IL-13 production. Treating ILC2s with adiponectin or an adiponectin receptor agonist (AdipoRon) activated AMPK and decreased IL-33-NF-κB signaling. AdipoRon also suppressed cold-induced thermogenic gene expression and energy expenditure in vivo. In contrast, adiponectin deficiency increased the ILC2 fraction and activation, leading to up-regulated thermogenic gene expression in adipose tissue of cold-exposed mice. ILC2 deficiency or blocking ILC2 function by neutralization of the IL-33 receptor with anti-ST2 diminished the suppressive effect of adiponectin on cold-induced adipose thermogenesis and energy expenditure. Taken together, our study reveals that adiponectin is a negative regulator of ILC2 function in adipose tissue via AMPK-mediated negative regulation of IL-33 signaling.

Sustained activation of autophagy suppresses adipocyte maturation via a lipolysis-dependent mechanism.

Dysregulation of macroautophagy/autophagy is implicated in obesity and insulin resistance. However, it remains poorly defined how autophagy regulates adipocyte development. Using adipose-specific rptor/raptor knockout (KO), atg7 KO and atg7 rptor double-KO mice, we show that inhibiting MTORC1 by RPTOR deficiency led to autophagic sequestration of lipid droplets, formation of LD-containing lysosomes, and elevation of basal and isoproterenol-induced lipolysis in vivo and in primary adipocytes. Despite normal differentiation at an early phase, progressive degradation and shrinkage of cellular LDs and downregulation of adipogenic markers PPARG and PLIN1 occurred in terminal differentiation of rptor KO adipocytes, which was rescued by inhibiting lipolysis or lysosome. In contrast, inactivating autophagy by depletion of ATG7 protected adipocytes against RPTOR deficiency-induced formation of LD-containing lysosomes, LD degradation, and downregulation of adipogenic markers in vitro. Ultimately, atg7 rptor double-KO mice displayed decreased lipolysis, restored adipose tissue development, and upregulated thermogenic gene expression in brown and inguinal adipose tissue compared to RPTOR-deficient mice in vivo. Collectively, our study demonstrates that autophagy plays an important role in regulating adipocyte maturation via a lipophagy and lipolysis-dependent mechanism. ABBREVIATIONS: ATG7: autophagy related 7; BAT: brown adipose tissue; CEBPB/C/EBPß: CCAAT enhancer binding protein beta; DGAT1: diacylglycerol O-acyltransferase 1; eWAT: epididymal white adipose tissue; iWAT: inguinal white adipose tissue; KO: knockout; LD: lipid droplet; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin kinase complex 1; PLIN1: perepilin 1; PNPLA2/ATGL: patatin-like phospholipase domain containing 2; PPARG/PPARγ: peroxisome proliferator activated receptor gamma; RPTOR: regulatory associated protein of MTOR complex1; TG: triglyceride; ULK1: unc-51 like kinase 1; UCP1: uncoupling protein 1; WAT: white adipose tissue.

Adipose mTORC1 Suppresses Prostaglandin Signaling and Beige Adipogenesis via the CRTC2-COX-2 Pathway.

Beige adipocytes are present in white adipose tissue (WAT) and have thermogenic capacity to orchestrate substantial energy metabolism and counteract obesity. However, adipocyte-derived signals that act on progenitor cells to control beige adipogenesis remain poorly defined. Here, we show that adipose-specific depletion of Raptor, a key component of mTORC1, promoted beige adipogenesis through prostaglandins (PGs) synthesized by cyclooxygenase-2 (COX-2). Moreover, Raptor-deficient mice were resistant to diet-induced obesity and COX-2 downregulation. Mechanistically, mTORC1 suppressed COX-2 by phosphorylation of CREB-regulated transcription coactivator 2 (CRTC2) and subsequent dissociation of CREB to cox-2 promoter in adipocytes. PG treatment stimulated PKA and promoted differentiation of progenitor cells to beige adipocytes in culture. Ultimately, we show that pharmacological inhibition or suppression of COX-2 attenuated mTORC1 inhibition-induced thermogenic gene expression in inguinal WAT in vivo and in vitro. Our study identifies adipocyte-derived PGs as key regulators of white adipocyte browning, which occurs through mTORC1 and CRTC2.