Increase In Adipocytes Research Articles

Stress memory of heart failure in hematopoietic niche promotes recurrence via adipocytic skewing of mesenchymal stromal cells

Abstract Background Heart failure (HF) is marked by recurrent acute decompensations, which poses significant treatment challenges in advanced stages. Our preceding work demonstrated that hematopoietic stem cells (HSCs) from HF-experienced mice induce cardiac fibrosis and dysfunction when transplanted, as a result of epigenetic alterations favoring myeloid hematopoiesis and impeding the differentiation of monocytes into cardiac mature macrophages. These findings hint at epigenetic modifications in HSCs as potential drivers of HF recurrence, suggesting their manipulation as a novel therapeutic strategy. However, the exact mechanisms by which HF-associated stress leads to these epigenetic changes remain unclear. Given the crucial role of bone marrow mesenchymal stromal cells (MSCs) in maintaining HSC stemness, this study explores the impact of cardiac stress on MSC function and its subsequent effect on HSCs. Purpose This study aims to elucidate the mechanisms behind the phenotypic changes in HSCs and to identify novel therapeutic targets to mitigate HF recurrence by investigating the role of MSCs in the hematopoietic niche under cardiac stress. Methods & Results Initially, we examined MSC phenotypic changes during HF using bulk and single-cell RNA sequencing. Results from transverse aortic constriction (TAC) model mice revealed a shift towards adipocyte differentiation under cardiac stress. Histological analyses confirmed an increase in adipocytes in TAC mice compared to controls, suggesting a stress-induced predisposition of MSCs towards adipocytic lineage commitment. This trend was further supported by ex vivo models using MSCs isolated from TAC mice. Notably, the proportion of adipocyte lineage-specific MSCs correlated with cardiac dysfunction severity. Subsequently, we assessed the impact of HF-conditioned MSCs on HF development by transplanting healthy HSCs with MSCs from control or TAC mice. Mice receiving HF-conditioned MSCs developed HF, evidenced by reduced ejection fraction and cardiac fibrosis. In these mice, a notable increase in HSC proliferation and a relative increase of myeloid cells within the peripheral blood were observed, along with an increase in proinflammatory cardiac macrophages. These findings suggest HF induces a "stress memory" in bone marrow MSCs. To test the potential of inhibiting adipocyte differentiation of MSCs in erasing this stress memory, we administered MSC phenotype-modulating agents to TAC mice, resulting in improved cardiac function and the disappearance of adipocytes from the bone marrow. Conclusions This study sheds light on how cardiac stress affects the bone marrow niche, leading to adipocytic skewing of MSCs and subsequent alterations in HSCs, thereby exacerbating cardiac dysfunction. The potential of targeting bone marrow niche components in HF treatment is highlighted.

Research progress on the role of lncRNA-miRNA networks in regulating adipogenic and osteogenic differentiation of bone marrow mesenchymal stem cells in osteoporosis.

Osteoporosis (OP) is characterized by a decrease in osteoblasts and an increase in adipocytes in the bone marrow compartment, alongside abnormal bone/fat differentiation, which ultimately results in imbalanced bone homeostasis. Bone marrow mesenchymal stem cells (BMSCs) can differentiate into osteoblasts and adipocytes to maintain bone homeostasis. Several studies have shown that lncRNAs are competitive endogenous RNAs that form a lncRNA-miRNA network by targeting miRNA for the regulation of bone/fat differentiation in BMSCs; this mechanism is closely related to the corresponding treatment of OP and is important in the development of novel OP-targeted therapies. However, by reviewing the current literature, it became clear that there are limited summaries discussing the effects of the lncRNA-miRNA network on osteogenic/adipogenic differentiation in BMSCs. Therefore, this article provides a review of the current literature to explore the impact of the lncRNA-miRNA network on the osteogenic/adipogenic differentiation of BMSCs, with the aim of providing a new theoretical basis for the treatment of OP.

Clodronate liposomes may biases MSC differentiation toward adipogenesis through activation of NLRP3

IntroductionClodronate-Liposomes (Clod-Lipo) injection after hematopoietic stem cell transplantation (HSCT) has been shown to be detrimental to hematopoietic reconstitution after transplantation, and our previous study showed that Clod-Lipo injection after HSCT increased adipocytes in the bone marrow cavity of mice after HSCT, but the reason for the large increase in adipocytes has not been clearly explained. The aim of this study was to investigate the source and mechanism of bone marrow cavity adipocytes after HSCT injection of Clod-Lipo. MethodsBALB/c mice received 7.5 Gy of total body irradiation followed by infusion of 5x106 bone marrow mononuclear cells from C57BL/6 via the tail vein. Clod-Lipo were injected through the tail vein on the first day after HSCT and every 5 days for the rest of the day. BALB/c mice were then divided into three groups: BMT, BMT + Clodronate-Liposomes (BMT + Clod-Lipo), and BMT + PBS-Liposomes (BMT + PBS-Lipo). Bone marrow pathological changes were detected by H&E staining, Western blot was used to detect the expression of NLRP3 and Caspase-1 in mouse bone marrow cells, and RT-qPCR was used to detect the expression levels of the key transcription factors peroxisome proliferator-activated receptor γ (PPAR-γ) and CCAAT/enhancer binding protein (C/EBPα) mRNA in bone marrow cells. Mouse mesenchymal stem cells (MSC) cultured in vitro were identified by flow cytometry, and adipocyte induction assays were performed using Clod-Lipo action for 24 h, Oil red staining was used to identify adipogenesis. Western blot was performed to detect NLRP3 and caspase-1 expression in MSC after Clod-Lipo action. Caspase-1 was blocked with Ac-YVAD-cmk (Ac-YV), followed by adipogenesis assay after 24 h of Clod-Lipo action to observe the change in the amount of adipogenesis. ResultsCompared with the other two groups, a significant increase in adipocytes was found in the Clod-Lipo group by HE staining, and increased expression of NLRP3 and Caspase-1 in mouse bone marrow cells was found by western Blot. By culturing MSC in vitro and performing adipogenesis assay after 24 h of Clod-Lipo action, it was found that adipogenesis was increased in the Clod-Lipo group, while the expression of NLRP3 and Caspase-1 was increased in MSCs, and adipogenesis assay was performed after 2 h of action using Caspase-1 inhibitor, and it was found that adipocytes was reduced. ConclusionsThe results of this study suggest that MSC are biased towards adipocyte generation in response to Clod-Lipo, a process that may be associated with activation of the NLRP3/caspase-1 pathway.

The Relationship of Sedentary Behavior and Sleep Duration to The Incidence of Obesity in Children under Five in Central Jakarta and The Review of Islamic Perspective

Introduction: Children under five should have their nutritional status checked regularly due to their susceptibility to diseases and nutritional problems. Inappropriate or excessive accumulation of fat, called obesity, can jeopardize their health. Assessment of nutritional status in obese toddlers can use anthropometric standards that are converted into Z-score values based on IMT/U with the category of obesity if the Z-score value is > +3 SD. Sedentary behaviour is when a person spends sitting or lying down with low energy expenditure outside sleep. Children and adolescents with high sedentary behaviour are prone to an increase in adipocytes that cause obesity. Children aged 3-5 years with poor sleep duration (<10 hours/day) are at greater risk of obesity. Methods: This type of research is quantitative with a cross-sectional design. The sample of this study was 70 children aged 2-5 years in Sawah Besar District, who were included in the inclusion criteria. Results: Out of 70 toddlers in Central Jakarta, 37 people (52.9%) were obese, and 33 (47.1%) were ordinary. Based on the results of statistical tests using the Chi-Square test, the p-value is <0.05, which can be concluded that there is a relationship between sedentary behaviour and obesity and a relationship between sleep duration and obesity. Conclusion: The research results show a significant relationship (p 0.03) between sedentary behaviour and obesity, with an Odd Ratio value of 3.137. There is also a meaningful relationship (p 0.016) between sleep duration and obesity, with an Odd Ratio value of 3.646 in Sawah Besar District, Central Jakarta toddlers.

Smoking Intensity Increases Diaphragm Muscle Injury: A Clinicopathologic Study.

Studying the effects of smoking intensity is important to evaluate the risk of tobacco use on a range of illnesses, such as as sarcopenia among the elderly. Thus, this study aimed to analyze the effects of pack-years of cigarette smoking on the diaphragm muscle (DIAm) histopathology of postmortem samples. Subjects were divided into three groups: never-smoker (n = 46); less than 30 pack-years of smoking (n = 12); and more than 30 pack-years of smoking (n = 30). Diaphragm samples were stained with Picrosirius red and hematoxylin and eosin stain for general structure. Participants with more than 30 pack-years of cigarette smoking had a significant increase in adipocytes, blood vessels and collagen deposit, as well as an increase in histopathological alterations. Pack-years of smoking was associated with DIAm injury. However, further clinicopathological studies are needed to confirm our findings.

Abstract P5-03-09: Cell composition changes in healthy breast tissue is associated with advancing age and epigenetic age acceleration

Abstract Introduction: Risk factors for breast cancer include advancing age, lifetime estrogen exposure, and breast density. DNA methylation-based estimates of age are elevated in breast tissue of healthy women compared with paired blood samples, and the degree of age acceleration is associated with lifetime estrogen exposure. However, no prior work has examined cell compositional changes associated with breast epigenetic aging. In this study we estimated the abundance of different cell types in healthy breast, computed using gene expression data, and investigate cell composition changes that accompany advancing chronologic age and breast epigenetic age acceleration. Methods: DNA/RNA were extracted (AllPrep, Qiagen) from breast tissue specimens from 192 healthy women aged 19-90 years who donated breast tissue to the Susan G. Komen Tissue Bank at the Indiana University Simon Comprehensive Cancer Center. Transcriptome analysis was performed using the QuantSeq 3’mRNA-SeqFWD kit to generate RNA sequencing libraries. DNA methylation age was estimated using beta-values from Illumina EPIC 850K array platform. Age acceleration is defined using the residual of a linear regression of methylation age on chronologic age. Cell deconvolution was performed using CIBERSORTx to estimate the abundance of adipocytes, luminal epithelial cells, basal myoepithelial cells, vascular endothelial cells, lymphatic endothelial cells, immune cells (dendritic cells & macrophages), pericytes & smooth muscle cells, and fibroblasts. We examined cell composition changes with chronologic age, and with age-adjusted measures of acceleration in 6 epigenetic clocks: the Horvath Pan-tissue, Hannum, Phenotypic, Grim, Skin & Blood, and Epigenetic Pacemaker clocks, as well as the DNA methylation-based estimate of telomere length, DNAmTL. Results: Advancing chronologic age was associated with an increase in the imputed proportion of adipocytes (R=0.40, p< 0.0001), vascular endothelial cells (R=0.23, p=0.0033), and immune cells (dendritic cells & macrophages) (R=0.29, p=0.00016), and a decrease in the proportion of luminal epithelial cells (R=-0.43, p< 0.0001), and basal myoepithelial cells (R=-0.27, p=0.00047). Epigenetic age acceleration was significantly associated with increases in proportions of luminal epithelial cells (p< 0.0001 for age-adjusted Hannum, Phenotypic, Grim, and Skin & Blood clocks, p< 0.05 for Pan-tissue) and basal myoepithelial cells (p< 0.0001 for Phenotypic and Skin & Blood clocks), and decreased proportions of adipocytes and vascular endothelial cells (p< 0.0001 for Hannum, Phenotypic, Grim, and Skin & Blood clocks, p< 0.05 for Pan-tissue). Conclusion: Using gene expression data in healthy female breast tissue, we identified significant changes in cell-type-specific abundance that accompany advancing chronologic age, with an increase in adipocytes and immune cells, and a decline in luminal epithelial cells and basal myoepithelial cells. By contrast, epigenetic age acceleration in breast tissue is associated with decreasing proportions of adipocytes and vascular endothelial cells and a rise in basal myoepithelial cells and luminal epithelial cells. Our findings suggest distinct patterns of cellular composition changes that accompany normal aging compared with accelerated aging in breast tissue. Citation Format: Mary E. Sehl, Wenbin Guo, Collin Farrell, Natascia Marino, Jill Henry, Anna Maria Storniolo, Jeanette Papp, Jingyi Li, Steve Horvath, Matteo Pellegrini, Patricia A. Ganz. Cell composition changes in healthy breast tissue is associated with advancing age and epigenetic age acceleration [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-03-09.

Anti-Obesity and Anti-Inflammatory Effects of Novel Carvacrol Derivatives on 3T3-L1 and WJ-MSCs Cells.

(1) Background: Obesity, a complex metabolic disease resulting from an imbalance between food consumption and energy expenditure, leads to an increase in adipocytes and chronic inflammatory conditions. The aim of this paper was to synthesize a small series of carvacrol derivatives (CD1-3) that are able to reduce both adipogenesis and the inflammatory status often associated with the progression of the obesity disease. (2) Methods: The synthesis of CD1-3 was performed using classical procedures in a solution phase. Biological studies were performed on three cell lines: 3T3-L1, WJ-MSCs, and THP-1. The anti-adipogenic properties of CD1-3 were evaluated using western blotting and densitometric analysis by assessing the expression of obesity-related proteins, such as ChREBP. The anti-inflammatory effect was estimated by measuring the reduction in TNF-α expression in CD1-3-treated THP-1 cells. (3) Results: CD1-3-obtained through a direct linkage between the carboxylic moiety of anti-inflammatory drugs (Ibuprofen, Flurbiprofen, and Naproxen) and the hydroxyl group of carvacrol-have an inhibitory effect on the accumulation of lipids in both 3T3-L1 and WJ-MSCs cell cultures and an anti-inflammatory effect by reducing TNF- α levels in THP-1 cells. (4) Conclusions: Considering the physicochemical properties, stability, and biological data, the CD3 derivative-obtained by a direct linkage between carvacrol and naproxen-resulted in the best candidate, displaying anti-obesity and anti-inflammatory effects in vitro.

Sinapic acid prevents adipogenesis by regulating transcription factors and exerts an anti-ROS effect by modifying the intracellular anti-oxidant system in 3T3-L1 adipocytes.

Objective(s):In this study, we tested the hypothesis that sinapic acid (SA), a naturally occurring hydroxycinnamic acid found in vegetables, cereal grains, and oilseed crops with various biological activities suppresses adipogenesis in 3T3-L1 adipocytes by down-regulating adipogenesis transcription factor. Materials and Methods:3T3-L1 adipocytes were treated with SA and evaluated by Oil Red O staining, triglyceride estimation, lipolysis, and reverse transcription-polymerase chain reaction. 3T3-L1 adipocytes were treated with various concentrations of SA (100 to 1000 μmol) during differentiation. Results:SA prevented an increase in adipocytes by reducing preadipocyte clonal expansion. ORO staining analyses revealed that SA reduced cytoplasmic lipid droplet accumulation in 3T3-L1 by 57% at the highest concentration of 1000 μmol without affecting cell viability. Furthermore, SA down-regulated the expression of peroxisome proliferator-activated receptor-gamma, CCAAT/enhancer-binding protein alpha, sterol regulatory element-binding protein 1c, and fatty acid synthase. ROS generated during adipogenesis was also attenuated by SA treatment by increasing antioxidant enzymes superoxide dismutase, catalase, and the cellular antioxidant glutathione. SA demonstrated no in vivo toxicity in the Drosophila melanogaster model. Conclusion:These results suggest that SA exerts anti-oxidant and anti-adipogenic effects and could be used as a functional nutraceutical ingredient in combatting obesity-related diseases.

PERSONALIZED APPROACH TO THE DIAGNOSIS OF CHILDREN WITH EXOGENOUS CONSTITUTIONAL OBESITY AGAINST THE BACKGROUND OF LEPTIN RESISTANCE

Abstract: Despite the fact that modern society is relatively well informed about the problem of childhood obesity, as well as a lot of work is being done by WHO to eliminate it, leading experts in the field of endocrinology believe that not always due importance is attached to the identification of risk factors, often the diagnosis of "Obesity" is not made in a timely manner and, accordingly, measures are not taken to prevent the development and progression of obesity in children. Modern parents do not consider the excess body weight of the child a pathology. Up to 70% of obese children are monitored only after 6-10 years from the appearance of the first signs of the disease. And on the part of specialists, additional research methods in obese children, which include the assessment of the hormonal profile, are recommended by leading experts only if secondary obesity is suspected. In this approach, it is overlooked that excess body weight and an increase in adipocytes in volume contributes to the production of a giant amount of leptin, which provokes a condition such as leptin resistance. This pathological condition is the leading cause of exogenous constitutional obesity in children today. For these reasons, leptin resistance in children all over the world is not diagnosed in a timely manner and therapy has been carried out unsuccessfully for years without affecting the etiology of the disease. The diagnostic method developed by us, taking into account the clinical signs of the disease, combining at least 5 clinical signs of exogenous constitutional obesity and an increase in the compliance index, allows us to establish leptin resistance without determining the level of leptin.

Osteal Macrophages and Megakaryocytes Increase Adipogenesis

Bone marrow adipose tissue (MAT) increases with aging and contributes to low bone density and skeletal fractures. However, the cells and factors within the bone marrow (BM) that regulate adipogenesis remain poorly understood. In the current study, we examined the role of osteal macrophages (OMs) and megakaryocytes (MKs) on the regulation of adipogenesis. We cultured murine osteoblasts/osteoblast progenitors (OBs from hereon) derived from neonatal calvarial cells (CCs, a combination of OBs and OMs) or OBs isolated by fluorescence activated cell sorting (FACS) in the presence or absence of fetal liver derived murine MK. The cells underwent induced adipogenesis for 5-7 days by supplementation of media with insulin, indomethacin, and dexamethasone, and then the number of adipocytes was quantified. We found that co-culturing MKs and OMs with OBs results in up to a 7.8-fold and 11.7-fold increase in adipocytes, respectively. We also elucidated that thrombopoietin (TPO), the major growth factor for MKs, inhibits adipogenesis in both OBs and CCs by approximately 60%. Similarly, we found that CCs and OBs derived from mice deficient in the TPO receptor, Mpl, had approximately 30% more adipocytes than their wild-type (WT) counterparts. Finally, in vitro findings were corroborated in vivo through quantification of MKs and adipocytes in mice in which MK number was elevated or reduced. Mice with significantly higher numbers of BM-residing MKs also had significantly higher numbers of BM-residing adipocytes. Because there is typically an inverse relationship between adipogenesis and osteogenesis, understanding ways to inhibit adipogenesis could lead to an increase in OB number and bone formation, which in turn could lead to new treatments for bone loss diseases such as osteoporosis.

CIDEA expression in SAT from adolescent girls with obesity and unfavorable patterns of abdominal fat distribution.

This study investigated whether variations in cell death-inducing DNA fragmentation factor alpha subunit-like effector A (CIDEA) mRNA expression and protein levels are modulated by the pattern of abdominal fat distribution in adolescent girls with obesity. This study recruited 35 adolescent girls with obesity and characterized their abdominal fat distribution by magnetic resonance imaging. Participants had only a periumbilical/abdominal (n = 14) or a paired abdominal and gluteal subcutaneous adipose tissue (SAT) biopsy (n = 21). CIDEA expression was determined by reverse transcription-polymerase chain reaction, CIDEA protein level by Western blot, and the turnover of adipose lipids and adipocytes by 2 H2 O labeling. In six girls, a second abdominal SAT biopsy was performed (after ~34.2 months) to explore the weight gain effect on CIDEA expression in abdominal SAT. CIDEA expression decreased in abdominal SAT from participants with high visceral adipose tissue (VAT)/(VAT+SAT); CIDEA inversely correlated with number of small adipocytes, with the increase in preadipocyte proliferation, and with adipogenesis. A strong inverse correlation was found between CIDEA protein level with the newly synthetized glycerol (r = -0.839, p = 0.0047). Following weight gain, an increase in adipocytes' cell diameter with a decrease in CIDEA expression and RNA-sequencing transcriptomic profile typical of adipocyte dysfunction was observed. Reduced expression of CIDEA in girls with high VAT/(VAT+SAT) is associated with adipocyte hypertrophy and insulin resistance.

TGF-β Signaling in Mesenchymal Progenitor Cells during Development Plays an Essential Role in the Emergence of the Bone Marrow Niche

Hematopoietic stem cell (HSC) quiescence and function are regulated, in part, by signals generated by stromal cells in the bone marrow. Mesenchymal stromal cells implicated in HSC maintenance include CXCL12-abudndant reticular (CAR) cells, osteolineage cells, and adipocytes, all of which, are derived from mesenchymal stem cells. The factors that regulate the growth, differentiation, and function of mesenchymal stems in the bone marrow are largely unknown. Here, we focus on transforming growth factor beta (TGF-β), which regulates osteoblast differentiation and has been implicated in the development of myelofibrosis in myeloproliferative neoplasms. We previously reported that constitutive deletion of Tgfbr2 (which abrogates all canonical TGF-β signaling) in mesenchymal stromal cells targeted by Osx-Cre results in marked alterations in the bone marrow microenvironment. These alterations include the following: 1) a 85-fold increase in adipocytes; 2) a 5-fold increase in CXCL12-abundant reticular (CAR) cells; and 3) the near absence of osteocalcin+ osteoblasts. Surprisingly, hematopoietic stem cells were only modestly reduced and had normal long-term repopulating and self-renewal capacity. These data suggest that TGF-β signaling plays a crucial role in determining the lineage commitment of mesenchymal progenitors.To investigate mechanisms by which TGF-β signaling regulates mesenchymal stromal cells, we first generated mice in which Tgfbr2 deletion is limited to Dmp1-Cre targeted stromal cells, which is mostly restricted to osteolineage cells. No alteration in stromal cells or hematopoiesis was observed. We next used a conditional Osx-Cre transgene to post-natally delete Tgfbr2 starting on P1. Surprisingly, these mice also had no alteration in osteoblasts, CAR cells, or adipocytes. Together, these experiments suggested the hypothesis that TGF-β signaling in mesenchymal progenitors during development may determine their lineage specification. To test this hypothesis, we analyzed Osx-Cre Tgfbr2fl/fl Ai9 mice during development; in these mice, Osx-Cre targeted cells express TdTomato. On E14.5 the nascent long-bones of control and Tgfbr2 -deleted mice appeared similar. Specifically, the primary ossification center contained a similar number and distribution of aggrecan-positive chondrocytes. Likewise, the number of TdTomato+ cells in the surrounding perichondrial “bone collar” was similar. However, on E16.5, a striking accumulation of perilipin-positive adipocytes was observed in Tgfbr2 -deleted but not control mice. Consistent with this finding, RNA expression profiling of Osx-Cre targeted (TdTomato-positive) cells sorted from the E16.5 long bones of Tgfbr2 -deleted mice showed a significant increase in adipocyte marker genes compared to control mice. Expression of peroxisome proliferator-activated receptor-gamma PPARG), a key transcription factor regulating adipogenesis, was increased 2-fold in Tgfbr2 -deleted cells. This is consistent with prior studies suggesting that TGF-β signaling negatively regulates PPARG expression.Collectively, these data show that TGF-β plays a key and non-redundant role in specifying the lineage commitment of mesenchymal progenitors in the bone marrow during development. Specifically, TGF-β suppresses the adipogenic potential of mesenchymal progenitors, possibly by regulating PPARG expression. Whether TGF-β signaling regulates bone marrow adiposity in adults, especially in response to aging or inflammation, is an open and interesting question. DisclosuresNo relevant conflicts of interest to declare.

“Obese Workshop”: Retrospective Study of the Advantages, Disease Preventions and Weight Losses

Obesity is termed as the pathology defined by excess body weight due to the increase in adipocytes. It can be visceral, close to the omentum, mesentery, and subcutaneous, accumulated in the hypodermis. It is a disease that entails metabolic, respiratory, locomotor, and cardiovascular problems, type II diabetes, cancer, and even mental problems. Established by the Body Mass Index (BMI) and defined from the relationship between weight (kg) and height (m) of individuals. In numerical terms, a person is considered obese when the BMI is equal to or greater than 30 kg/m. This retrospective study took into account the more than 30 years that the coordinator of this work has devoted to morbidly obese people and all his 47 years of experience in medicine. The first obese person of his career was 41 years old and weighed 210 kg. As soon as she arrived at the hospital, she said: “Doctor, I am here, because I need to enter a ‘workshop’, to repair my body”. From that moment on, the name “workshop” became part of a fantastic project with obese people called “Obese Workshop”. Over time, the number of patients with this comorbidity has only increased, reaching, once, the point of speaking to 325 interested parties in a single day and in the same hall. In order to achieve satisfactory results, we have established a number of tests, by which we could diagnose several reasons that cause obesity. We selected randomly 20 patients of both sexes, morbidly obese, operated in 2013. We do not take into account age, race, creed, or social status.

Overaccumulation of Fat Caused Rapid Reproductive Senescence but not Loss of Ovarian Reserve in ob/ob Mice

Ovarian reserve and fertility are reduced by aging and a poor energy balance. To date, the relationships of high energy accumulation and aging with the ovarian reserve have not been elucidated. Here, the effects of obesity on the aging ovarian reserve were evaluated in a leptin-deficient (ob/ob) mouse model. Abnormal estrous cyclicity appeared as early as 6 weeks and worsened with aging. The blood level patterns of 17β-estradiol (E2), testosterone (T), and progesterone (P4) with aging were similar between lean and ob/ob mice. The blood level of E2 but not P4 or T was similar at 24 weeks. Many more atretic follicles but fewer corpora lutea were observed in ob/ob mice than in lean mice within all age groups. Anti-Müllerian hormone (Amh) mRNA levels were similar between genotypes. Dazl, Stra8, and ZP3 mRNAs were highly expressed in ob/ob mice after 12 weeks. Sohlh1 and Ybx2 mRNAs were highly expressed at 24 weeks in ob/ob compared with lean mice. In addition, SOHLH1-positive primordial follicle counts were significantly increased in ob/ob mice at 24 weeks. The proportions of AMH-positive secondary and small antral follicles were similar between genotypes. Together, these results show that the ovarian reserve lasts longer in ob/ob mice than in lean mice, suggesting that the loss of normal physiological or physical status causes decreased fertility at a young age in ob/ob mice and that an increase in adipocytes without leptin, as in ob/ob mice, can improve the ovarian reserve. Such knowledge can be applied to understanding reproductive dysfunction.

CAMP-dependent protein kinase A in grass carp Ctenopharyngodon idella: Molecular characterization, gene structure, tissue distribution and mRNA expression in endoplasmic reticulum stress-induced adipocyte lipolysis.

Protein kinase A (PKA), one of the most widely studied protein kinases, has many functions in cells, including regulating the metabolism of sugar and lipid. Here we identified nine isoforms of the PKA family in grass carp Ctenopharyngodon idella and obtained their complete coding sequences (CDS), including PRKACAa, PRKACAb, PRKACBa, PRKACBb, PRKAR1A, PRKAR1B, PRKAR2Aa, PRKAR2Ab and PRKAR2B, and PRKACA, PRKACB and PRKAR2A, which may experience fish-specific genome duplication. Sequence analysis showed that the predicted protein structures of PKA gene family members in grass carp were different. Grass carp PRKACAa, PRKACAb, PRKACBa, and PRKACBb contained serine/threonine protein kinases, while PRKAR1A, PRKAR1B, PRKAR2Aa, PRKAR2Ab and PRKAR2B contained two cyclic nucleotide-monophosphate binding domains. PRKACAa, PRKACBa, PRKACBb, PRKAR1A, PRKAR1B and PRKAR2Aa contained 10 coding exons, while PRKACAb and PRKAR2Ab consisted of 12 coding exons and 5 coding exons, respectively. The messenger RNA (mRNA) of the nine PKA isoforms was detected in a wide range of tissues, but their abundance showed tissue-dependent expression patterns. In tunicamycin-induced adipocyte lipolysis, only the mRNA levels of PRKACAb and PRKACBa showed a significant increase in adipocyte (p<.05), indicating that nine PKA isoforms may serve somewhat different roles in endoplasmic reticulum (ER) stress-mediated lipolysis in fish. These results suggested that nine grass carp PKA isoforms may play different roles in tissues, and their expression levels were differently modulated by ER stress in adipocyte.

Identification and characterization of two isoforms of acyl-coenzyme A oxidase 1 gene and their expression in fasting-induced grass carp Ctenopharyngodon idella adipocyte lipolysis.

Acyl-coenzyme A oxidases 1 (ACOX1) is the first rate-limiting enzyme responsible for peroxisomal β-oxidation. In the present study, two mRNA variants, ACOX1a and ACOX1b, transcribed from a single gene, were for the first time isolated and characterized from grass carp Ctenopharyngodon idella, both encoding putative peptides of 660 amino acids. Analysis of the exon-intron structures clarified that grass carp ACOX1a and ACOX1b comprise 14 coding exons and correspond to 3a and 3b isoforms of exon 3 splicing variants. Both ACOX1a and ACOX1b mRNAs were expressed in a wide range of tissues, but the abundance of each ACOX1 mRNA showed the tissue-dependent expression patterns. Time-course analysis of ACOX1 expressions indicated that the level of ACOX1a mRNA reached an almost maximal level at day 2, while that of ACOX1b mRNA reached an almost maximal level at day 8 during grass carp primary preadipocyte differentiation. In fasting-induced adipocyte lipolysis, only ACOX1a showed a significant increase in adipocyte, indicating that two ACOX1 isoforms may serve somewhat different roles in the peroxisomal β-oxidation. These results suggested that grass carp ACOX1a and ACOX1b were differently modulated by fasting in adipocyte. In addition, we found that mitochondrial β-oxidation might dominate at the early stage of fasting in adipocytes, indicating that mitochondria and peroxisomes might possess different capacities in fasting-induced adipocytes fatty acid oxidation.

OSBPL2 Is Required for the Binding of COPB1 to ATGL and the Regulation of Lipid Droplet Lipolysis.

SummaryThe accumulation of giant lipid droplets (LDs) increases the risk of metabolic disorders including obesity and insulin resistance. The lipolysis process involves the activation and transfer of lipase, but the molecular mechanism is not completely understood. The translocation of ATGL, a critical lipolysis lipase, from the ER to the LD surface is mediated by an energy catabolism complex. Oxysterol-binding protein-like 2 (OSBPL2/ORP2) is one of the lipid transfer proteins that regulates intracellular cholesterol homeostasis. A recent study has proven that Osbpl2−/− pigs exhibit hypercholesterolemia and obesity phenotypes with an increase in adipocytes. In this study, we identified that OSBPL2 links the endoplasmic reticulum (ER) with LDs, binds to COPB1, and mediates ATGL transport. We provide important insights into the function of OSBPL2, indicating that it is required for the regulation of lipid droplet lipolysis.

Insights into lipid accumulation in skeletal muscle in dysferlin-deficient mice

Loss of dysferlin (DYSF) protein in humans results in limb-girdle muscular dystrophy 2B, characterized by progressive loss of muscles in the distal limbs with impaired locomotion. The DYSF-null (Bla/J) mouse develops severe steatotic muscles upon aging. Here, we report a marked increase in adipocytes, especially in the psoas and gluteus muscles but not in the soleus and tibialis anterior muscles in aged Bla/J mice compared with WT mice. There was a robust upregulation in the mRNA expression of enzymes involved in lipogenesis and triacylglycerol (TAG) synthesis pathways in the steatotic skeletal muscles. Lipidomic analysis of the steatotic skeletal muscles revealed an increase in several molecular species of TAG, although it is unclear whether it was at the expense of phosphatidylcholine and phosphatidylserine. The adipocytes in steatotic muscles were extramyocellular, as determined by the increased expression of caveolin 1 (a cellular marker for adipocytes) and lipid-droplet protein, perilipin 1. This increase in adipocytes occured as a consequence of the loss of myocytes.

Bone loss from Wnt inhibition mitigated by concurrent alendronate therapy

Dysregulated Wnt signaling is associated with the pathogenesis of cancers, fibrosis, and vascular diseases. Inhibition of Wnt signaling has shown efficacy in various pre-clinical models of these disorders. One of the key challenges in developing targeted anti-cancer drugs is to balance efficacy with on-target toxicity. Given the crucial role Wnts play in the differentiation of osteoblasts and osteoclasts, acute inhibition of Wnt signaling is likely to affect bone homeostasis. In this study, we evaluated the skeletal effect of small molecule inhibitor of an o-acyl transferase porcupine (PORCN) that prevents Wnt signaling by blocking the secretion of all Wnts. Micro-computed tomography and histomorphometric evaluation revealed that the bones of mice treated with two structurally distinct PORCN inhibitors LGK974 and ETC-1922159 (ETC-159) had loss-of-bone volume and density within 4 weeks of exposure. This decreased bone mass was associated with a significant increase in adipocytes within the bone marrow. Notably, simultaneous administration of a clinically approved anti-resorptive, alendronate, a member of the bisphosphonate family, mitigated loss-of-bone mass seen upon ETC-159 treatment by regulating activity of osteoclasts and blocking accumulation of bone marrow adipocytes. Our results support the addition of bone protective agents when treating patients with PORCN inhibitors. Mitigation of bone toxicity can extend the therapeutic utility of Wnt pathway inhibitors.

Evaluation of the rivastigmine role against botulinum toxin-A-induced osteoporosis in albino rats: A biochemical, histological, and immunohistochemical study.

The present study aimed to evaluate the role of rivastigmine against the effect of a single unilateral botulinum toxin-A (BTX-A) injection on the bone and bone marrow of adult albino rats 4 weeks after injection. Twenty-four Wistar albino rats were divided into four equal groups: group I, which received distilled water; group II, which received rivastigmine (0.3 mg/kg daily, intraperitoneally for 4 weeks); group III, which received BTX-A (4 IU in 0.2 mL physiological saline) single dose, intramuscularly; and group IV, which received BTX-A + rivastigmine. The results revealed that BTX-A induced a significant decrease in the calcium level with a significant increase in the phosphorus, alkaline phosphatase, C-reactive protein, and tumor necrosis factor α levels in serum. Furthermore, a significant increase in malondialdehyde with a significant decrease in reduced glutathione activities in both bone and bone marrow. Histologically, a distortion and thinning out of the compact bone and trabeculae of cancellous bone of the rat femur in the BTX-A group with an increase in adipocytes in adjacent bone marrow were detected. Immunohistochemically, Cluster of Differentiation 68 (CD68) showed a significant increase in both osteoclasts and bone marrow macrophage. Rivastigmine treatment could relieve the toxic effects induced by BTX-A. In conclusion, rivastigmine has a protective effect against the hazardous effects of BTX-A on bone and bone marrow.