Programming mediated by fatty acids affects uncoupling protein 1 (UCP-1) in brown adipose tissue

White-brown adipose tissue interplay in polycystic ovary syndrome: Therapeutic avenues

This study highlights the therapeutic potential of activating brown adipose tissue (BAT) for managing polycystic ovary syndrome (PCOS), a prevalent endocrine disorder associated with metabolic and reproductive abnormalities. BAT plays a crucial role in regulating energy expenditure and systemic insulin sensitivity, making it an attractive target for the treatment of obesity and metabolic diseases. Recent research suggests that impaired BAT function and mass may contribute to the link between metabolic disturbances and reproductive issues in PCOS. Additionally, abnormal white adipose tissue (WAT) can exacerbate these conditions by releasing adipokines and nonesterified fatty acids. In this review, we explored the impact of WAT changes on BAT function in PCOS and discussed the potential of BAT activation as a therapeutic strategy to improve PCOS symptoms. We propose that BAT activation holds promise for managing PCOS; however, further research is needed to confirm its efficacy and to develop clinically feasible methods for BAT activation.

N-carbamoyl aspartate reduced body weight by stimulating the thermogenesis of iBAT

Uridine has formerly been shown to alleviate obesity and hepatic lipid accumulation. N-carbamoyl aspartate (NCA) provides carbon atoms to uridine in de novo pyrimidine biosynthesis pathway. However, whether NCA is involved in the lipid metabolism remains elusive. Here we showed that NCA supplementation significantly decreased (P < 0.05) serum cholesterol (CHOL), high-density lipoprotein (HDL), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) levels of mice, and significantly increased (P < 0.05) relative mRNA expression of genes related to the synthesis of pyrimidine nucleotides and polyunsaturated fatty acids. Besides, supplemented with NCA significantly decreased body weight and area under the curve (AUC), and increased body temperature in the high-fat diet fed mice. For further, relative protein expression of uridine monophosphate synthase (UMPS), sterol regulatory element-binding protein 1(SREBP-1) and phosphorylated hormone-sensitive triglyceride lipase (P-HSL) in the liver, and uncoupling protein 1 (UCP-1) in interscapular brown adipose tissue (iBAT) also showed upregulated in the high-fat diet fed mice. Thus, NCA promoted de novo synthesis of pyrimidine and polyunsaturated fatty acid, and reduced body weight by stimulating high-fat diet-induced thermogenesis of iBAT.

Role of Hormones During Gestation and Early Development: Pathways Involved in Developmental Programming

Accumulating evidence suggests that an altered maternal milieu and environmental insults during the intrauterine and perinatal periods of life affect the developing organism, leading to detrimental long-term outcomes and often to adult pathologies through programming effects. Hormones, together with growth factors, play critical roles in the regulation of maternal-fetal and maternal-neonate interfaces, and alterations in any of them may lead to programming effects on the developing organism. In this chapter, we will review the role of sex steroids, thyroid hormones, and insulin-like growth factors, as crucial factors involved in physiological processes during pregnancy and lactation, and their role in developmental programming effects during fetal and early neonatal life. Also, we will consider epidemiological evidence and data from animal models of altered maternal hormonal environments and focus on the role of different tissues in the establishment of maternal and fetus/infant interaction. Finally, we will identify unresolved questions and discuss potential future research directions.

Mitochondrial respiration in thoracic perivascular adipose tissue of diabetic mice

Introduction

Thoracic perivascular adipose tissue (tPVAT) has a phenotype resembling brown AT. Dysfunctional tPVAT appears to be linked to vascular dysfunction.

Methods

We evaluated uncoupling protein 1 (UCP1) expression by Western blot, oxidative stress by measuring lipid peroxidation, the antioxidant capacity by HPLC and spectrophotometry, and mitochondrial respiration by high-resolution respirometry (HRR) in tPVAT, compared to inguinal white AT (iWAT), obtained from non-diabetic (NDM) and streptozocin-induced diabetic (STZ-DM) mice. Mitochondrial respiration was assessed by HRR using protocol 1: complex I and II oxidative phosphorylation (OXPHOS) and protocol 2: fatty acid oxidation (FAO) OXPHOS. OXPHOS capacity in tPVAT was also evaluated after UCP1 inhibition by guanosine 5'-diphosphate (GDP).

Results

UCP1 expression was higher in tPVAT when compared with iWAT in both NDM and STZ-DM mice. The malondialdehyde concentration was elevated in tPVAT from STZ-DM compared to NDM mice. Glutathione peroxidase and reductase activities, as well as reduced glutathione levels, were not different between tPVAT from NDM and STZ-DM mice but were lower compared to iWAT of STZ-DM mice. OXPHOS capacity of tPVAT was significantly decreased after UCP1 inhibition by GDP in protocol 1. While there were no differences in the OXPHOS capacity between NDM and STZ-DM mice in protocol 1, it was increased in STZ-DM compared to NDM mice in protocol 2. Moreover, complex II- and FAO-linked respiration were elevated in STZ-DM mice under UCP1 inhibition.

Conclusions

Pharmacological therapies could be targeted to modulate UCP1 activity with a significant impact in the uncoupling of mitochondrial bioenergetics in tPVAT.

PGC-1α affects skeletal muscle and adipose tissue development by regulating mitochondrial biogenesis

The discovery and interpretation of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) protein in mitochondrial biogenesis, skeletal muscle and adipose tissue development has broad research prospects, so it is important to review the related studies of PGC-1α in detail and comprehensively. PGC-1α is a protein composed of 798 amino acids (aa) with a molecular weight of about 91 kDa. PGC-1α is involved in the operation of the respiratory chain by combining with deacetylase and phosphorylase to bind some nuclear receptors. In addition, PGC-1α affects skeletal muscle and adipose metabolism by regulating mitochondrial oxidative phosphorylation. Recently, new data suggest that regulating mitochondrial metabolism in adipose tissue may be an effective adjunct to the treatment of obesity. In addition, dietary resveratrol, which has an effective anti-obesity effect, has been shown to promote mitochondrial biosynthesis by activating AMPK/PGC-1α axis, as well as to regenerate muscle damaged by obesity. In this review, we combined previous studies to explore the latest studies, showing that PGC-1α can regulate mitochondrial biogenesis and is regulated by AMPK and SIRT1. Furthermore, PGC-1α is a favored protein, which not only regulates muscle fiber type, inhibits muscle atrophy, but also participates in browning of white adipose tissue (WAT) and regulates body heat production. So, we concluded that PGC-1α is a key gene in mitochondrial biogenesis and plays an important role in the regulation and regulation of mitochondrial biogenesis along with other genes involved in the process. Meanwhile, PGC-1α acts as a core metabolic regulator in adipose tissue and skeletal muscle. This review comprehensively summarizes a large number of research findings. First, the role of PGC-1α in mitochondrial biogenesis was clarified, and then the key role of PGC-1α in the development of skeletal muscle and adipose tissue was reevaluated. Furthermore, the role of PGC-1α in some human diseases was discussed. Finally, the role of PGC-1α as a major gene in poultry was pointed out, and the future research direction was proposed.

Lipoxin A4 promotes adipogenic differentiation and browning of mouse embryonic fibroblasts

Recently, it has been irrefutably discovered that brown adipocytes dissipate energy as heat and protect against obesity. Researchers make great efforts to explore approaches for its activation. Lipoxin A4 (LXA4) has been proven to reverse adipose tissue inflammation and improve insulin resistance, but its function on brown adipocyte differentiation has been poorly understood, which therefore to be investigated in the present study. Mouse embryonic fibroblasts (MEFs) were induced and differentiated to model brown adipocytes, and treated with LXA4 at 0, 1, 5, and 10 nM for 0-14 d. Afterwards, Oil Red O staining detected lipid droplets. In differentiated MEFs with or without LXA4 (10 nM) treatment, western blot and quantitative real-time polymerase chain reaction (qRT-PCR) assessed adipocyte browning marker uncoupling protein 1 (UCP-1), and brown adipogenesis markers peroxisome proliferator-activated receptor gamma (PPARγ), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), cyclooxygenase-2 (COX-2), and positive regulation domain containing 16 (PRDM16) as well as lipogenic genes of stearoyl-CoA desaturase 1 (SCD1), fatty acid synthase (FASN), glucose transporter type 4 (GLUT4), and carbohydrate response element binding protein (ChREBP). The induced differentiation of MEFs toward brown adipocytes was successful. LXA4 promoted intracellular accumulation of lipid droplets of induced cells and increased UCP-1 expression in a dose- or time-dependent manner. Under the administration of LXA4, brown adipogenesis markers and lipogenic genes were further upregulated. LXA4 made a contribution to induce differentiation of MEFs to brown adipocytes, which could be regarded a new drug target for obesity management.

Integrated Analysis of Liver Transcriptome, miRNA, and Proteome of Chinese Indigenous Breed Ningxiang Pig in Three Developmental Stages Uncovers Significant miRNA-mRNA-Protein Networks in Lipid Metabolism

Liver is an important metabolic organ of mammals. During each transitional period of life, liver metabolism is programmed by a complex molecular regulatory system for multiple physiological functions, many pathways of which are regulated by hormones and cytokines, nuclear receptors, and transcription factors. To gain a comprehensive and unbiased molecular understanding of liver growth and development in Ningxiang pigs, we analyzed the mRNA, microRNA (miRNA), and proteomes of the livers of Ningxiang pigs during lactation, nursery, and fattening periods. A total of 22,411 genes (19,653 known mRNAs and 2758 novel mRNAs), 1122 miRNAs (384 known miRNAs and 738 novel miRNAs), and 1123 unique proteins with medium and high abundance were identified by high-throughput sequencing and mass spectrometry. We show that the differences in transcriptional, post-transcriptional, or protein levels were readily identified by comparing different time periods, providing evidence that functional changes that may occur during liver development are widespread. In addition, we found many overlapping differentially expressed genes (DEGs)/differentially expressed miRNAs (DEMs)/differentially expressed proteins (DEPs) related to glycolipid metabolism in any group comparison. These overlapping DEGs/DEMs/DGPs may play an important role in functional transformation during liver development. Short Time-series Expression Miner (STEM) analysis revealed multiple expression patterns of mRNA, miRNA, and protein in the liver. Furthermore, several diverse key Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including immune defense, glycolipid metabolism, protein transport and uptake, and cell proliferation and development, were identified by combined analysis of DEGs and DGPs. A number of predicted miRNA–mRNA–protein pairs were found and validated by qRT-PCR and parallel reaction monitoring (PRM) assays. The results provide new and important information about the genetic breeding of Ningxiang pigs, which represents a foundation for further understanding the molecular regulatory mechanisms of dynamic development of liver tissue, functional transformation, and lipid metabolism.

Gut Microbiota: Novel Therapeutic Target of Ginsenosides for the Treatment of Obesity and Its Complications

Obesity, generally characterized by excessive lipid accumulation, is a metabolic threat worldwide due to its rapid growth in global prevalence. Ginsenosides are crucial components derived from natural plants that can confer metabolic benefits for obese patients. Considering the low bioavailability and degradable properties of ginsenosides in vivo, it should be admitted that the mechanism of ginsenosides on anti-obesity contribution is still obscure. Recently, studies have indicated that ginsenoside intervention has beneficial metabolic effects on obesity and its complications because it allows for the correction of gut microbiota dysbiosis and regulates the secretion of related endogenous metabolites. In this review, we summarize the role of gut microbiota in the pathogenetic process of obesity, and explore the mechanism of ginsenosides for ameliorating obesity, which can modulate the composition of gut microbiota by improving the metabolism of intestinal endogenous substances and alleviating the level of inflammation. Ginsenosides are expected to become a promising anti-obesity medical intervention in the foreseeable clinical settings.

Anti-obesity effects of red seaweed, Plocamium telfairiae, in C57BL/6 mice fed a high-fat diet

This study aimed to demonstrate the anti-obesity effect of Plocamium telfairiae (PT), a red seaweed. Different percentages of ethanol (0%, 20%, 40%, 60%, 80%, and 100%) were used for the preparation of PT extract. Furthermore, 3T3-L1 cells were used to determine the percentage of ethanol for optimal anti-adipogenesis of PT, and the anti-obesity properties of the optimized extract of PT (PTE) (40%) was assessed in obese mice. The results indicate that 40% ethanol extract (40 PTE) significantly decreased fat accumulation and suppressed the expression of major adipogenesis factors such as peroxisome proliferator-activated receptor-γ (PPAR-γ), sterol regulatory element-binding protein 1 (SREBP-1), CCAAT/enhancer-binding protein (C/EBP)-α, and phosphorylated ACC (pACC) in 3T3-L1 cells. Furthermore, in the high-fat diet-induced obese mice, 40 PTE significantly reduced the weights of white adipose tissue, as well as the levels of triglyceride, total cholesterol, adiponectin, and insulin in the serum. Liver histopathology showed that steatosis decreased in all the PTE treatment groups. The adipogenesis-related proteins, PPAR-γ and SREBP-1, were also significantly decreased in PTE treatment groups. Additionally, 40 PTE increased mRNA expression of mitochondrial uncoupling proteins (UCP)-1 and UCP-3 in brown adipose tissue. These findings provide evidence that 40 PTE can alleviate lipid droplet accumulation in 3T3-L1 adipocytes and obese C57BL/6 mice, indicating that PTE has strong anti-obesity effects and could be used as a therapeutic agent or a component of pharmaceutical drugs and functional foods.

Impact of Maternal Obesity on the Metabolism and Bioavailability of Polyunsaturated Fatty Acids during Pregnancy and Breastfeeding

Prenatal and postnatal development are closely related to healthy maternal conditions that allow for the provision of all nutritional requirements to the offspring. In this regard, an appropriate supply of fatty acids (FA), mainly n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), is crucial to ensure a normal development, because they are an integral part of cell membranes and participate in the synthesis of bioactive molecules that regulate multiple signaling pathways. On the other hand, maternal obesity and excessive gestational weight gain affect FA supply to the fetus and neonate, altering placental nutrient transfer, as well as the production and composition of breast milk during lactation. In this regard, maternal obesity modifies FA profile, resulting in low n-3 and elevated n-6 PUFA levels in maternal and fetal circulation during pregnancy, as well as in breast milk during lactation. These modifications are associated with a pro-inflammatory state and oxidative stress with short and long-term consequences in different organs of the fetus and neonate, including in the liver, brain, skeletal muscle, and adipose tissue. Altogether, these changes confer to the offspring a higher risk of developing obesity and its complications, as well as neuropsychiatric disorders, asthma, and cancer. Considering the consequences of an abnormal FA supply to offspring induced by maternal obesity, we aimed to review the effects of obesity on the metabolism and bioavailability of FA during pregnancy and breastfeeding, with an emphasis on LCPUFA homeostasis.

Trans-fatty acids aggravate anabolic steroid-induced metabolic disturbances and differential gene expression in muscle, pancreas and adipose tissue

AIMS

Although anabolic steroids (AS) and trans-fatty acids overload exerts systemic toxicity and are independent risk factors for metabolic and cardiovascular disorders, their interaction remains poorly understood. Thus, we investigated the impact of a diet rich in trans-fatty acids (HFD) combined with AS on glycemic control, lipid profile, adipose tissue, skeletal muscle and pancreas microstructure and expression of genes involved in energy metabolism.

MAIN METHODS

Forty-eight C57BL/6 mice were randomized into 6 groups treated for 12 weeks with a standard diet (SD) or a diet rich in C18:1 trans-fatty isomers (HFD), alone or combined with 10 or 20 mg/kg testosterone cypionate (AS).

KEY FINDINGS

Our results indicated that AS improved glycemic control, upregulated gene expression of Glut-4 and CPT-1 in skeletal muscle, FAS, ACC and UCP-1 in adipose tissue. AS also reduced total and LDL cholesterol in mice fed a SD. When combined with the HFD, AS was unable to induce microstructural adaptations in adipose tissue, pancreatic islets and β-cells, but potentiated GCK and Glut-2 (pancreas) and Glut-4 and CPT-1 (skeletal muscle) upregulation. HFD plus AS also downregulated FAS and ACC gene expression in adipose tissue. Combined with HFD, AS increased triacylglycerol circulating levels, improved insulin sensitivity and glycemic control in mice.

SIGNIFICANCE

Our findings indicated that HFD and AS can interact to modulates glycemic control and lipid profile by a mechanism potentially related with a reprogramming of genes expression in organs such as the pancreas, adipose tissue and skeletal muscle.