Clinical ketosis is a crucial metabolic disease in dairy cows that is often accompanied by severe lipolysis and inflammation in adipose tissue. Our previous study suggested that the fold change of calmodulin (CaM) was upregulated 2.401-fold in the adipose tissue of cows with clinical ketosis. Therefore, we hypothesize that CaM may regulate lipolysis and inflammatory responses in clinical ketosis cows. To verify the hypothesis, we conducted a thorough veterinary assessment of clinical symptoms and serum β-hydroxybutyrate (BHB) concentration before collecting subcutaneous adipose tissue samples from six healthy and six clinically ketotic Holstein cows at 17 ± 4 days postpartum. Commercial kits were used to test the abundance of BHB, Non-esterified fatty acid (NEFA), Liver function index (LFI), interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α). We found that Clinical ketosis cows had higher levels of BHB, NEFA, LFI, IL-6, IL-1β, TNF-α, and lower glucose levels compared to healthy cows. Furthermore, the abundance of CaM, toll-like receptor 4 (TLR4), inhibitor of nuclear factor κB kinase subunit β (IKK), phosphorylated nuclear factor κB/nuclear factor κB, (p-NF-κB/NF-κB), adipose triglyceride lipase (ATGL) and phosphorylated hormone-sensitive lipase/hormone-sensitive lipase (p-HSL/HSL) were increased, while that of perilipin-1 (PLIN1) was decreased in the adipose tissue of cows with clinical ketosis. To investigate the mechanistic underlying the responses, we isolated the primary bovine adipocytes from the adipose tissue of healthy cows and induced the inflammatory response mediated by TLR4/IKK/NF-κB with lipopolysaccharide (LPS), in addition to treating with CaM overexpression adenovirus and CaM small interfering RNA. In vitro, LPS upregulated the abundance of CaM, TLR4, IKK, NF-κB, ATGL, p-HSL/HSL, and CaM and downregulated PLIN1. CaM silencing downregulated the abundance of LPS-activated p-HSL/HSL, TLR4, IKK, and NF-κB and upregulated PLIN1 in bovine adipocytes, except for ATGL. By contrast, CaM overexpression upregulated the abundance of LPS-activated p-HSL/HSL, TLR4, IKK, and NF-κB and downregulated PLIN1 expression in bovine adipocytes. In summary, these data suggest that CaM promotes lipolysis in adipocytes through HSL and PINL1 while activating the TLR4/IKK/NF-κB inflammatory pathway to promote an inflammatory response. There is a positive feedback loop between CaM, lipolysis, and inflammation. Overall, inhibiting CaM may act as an adaptive mechanism to alleviate metabolic dysregulation in adipose tissue, contributing to relief from lipolysis and inflammatory response.

The number of obese people worldwide is rising dramatically, with 51% of the global population expected to be obese or overweight by 2035. And it is usually involved in a variety of chronic diseases, including diabetes, hypertension, cardiovascular and cerebrovascular diseases. In the process of obesity, adipose tissue expands indefinitely, which induces metabolic dysfunction. Here, we confirm the role of succinate in the intervention of obesity. Through adding succinate to drinking water, high-fat diet induced obese mice were associated with the lower fat mass, and improved glucose tolerance and energy expenditure. These metabolic changes are accompanied by increased expression of lipolysis genes and decreased lipogenesis genes, especially in subcutaneous adipose tissue. In summary, supplement of succinate improves lipid deposition and metabolic health in obese mice.

Alcoholic liver disease (ALD) develops when the immunotolerant environment of the liver is compromised due to excessive alcohol consumption. ALD progression involves variations in the expression of multiple genes, resulting in liver inflammation and the development of a leaky gut. Molecular mechanism involved for ALD progression is still unclear, and due to that there are currently no FDA-approved drugs available for its treatment. In this study, the protective effects of Graphene oxide nanoparticles (GO) was investigated against ethanol-induced damage in the gut-liver axis in in vitro. GO was synthesized using a modified Hummer's method and characterization was done. Given the general concerns regarding nanoparticle toxicity, assessment of cell viability, lipid accumulation, DNA damage, cell death, and the generation of reactive oxygen species (ROS) were conducted using various techniques. Furthermore, gene expression of pro- and anti-inflammatory cytokines was done using RT-qPCR. The findings revealed that GOs promoted cell viability even against ethanol treatment. Additionally, lipid accumulation significantly decreased when cells were treated with GO alongside ethanol compared to ethanol treatment alone, with similar trends observed for other assays. Gene expression analysis indicated that GO treatment reduced the expression of proinflammatory cytokines while enhancing the expression of antioxidant genes. Moreover, GO treatment led to improvements in gut permeability and a reduction in proinflammatory cytokines in colon cells damaged by ethanol. These findings suggest that GO holds promise as a drug carrier, exhibiting no observed toxic effects. By shedding light on the protective effects of GO against ethanol-induced damage, this study contributes to the burgeoning field of nanoparticle-mediated therapy for ALD.

Piceatannol (PIC), a natural analog of resveratrol, has various biological functions. We previously reported that PIC had an anti-obesity effect only in ovariectomized mice. While ovariectomized mice have low phosphorylation levels of hormone-sensitive lipase (pHSL) at Ser563, we found that PIC increased those levels. Here, we investigated the effect of PIC using 3T3-L1 adipocytes to clarify the mechanism by which PIC activates HSL. First, PIC was confirmed to induce HSL phosphorylation at Ser563 in 3T3-L1 cells as in vivo experiments showed. pHSL (Ser563) is believed to be activated through the β-adrenergic receptor (β-AR) and protein kinase A (PKA) pathway; however, the addition of a selective inhibitor of β-AR did not inhibit the effect of PIC. The addition of PKA inhibitor with PIC blocked pHSL (Ser563), suggesting that PIC’s effects are mediated by PKA from a different pathway than β-AR. The addition of G15, a selective inhibitor of the G protein-coupled estrogen receptor (GPER), lowered HSL activation by PIC. Furthermore, PIC inhibited insulin signaling and did not induce pHSL (Ser565), which represents its inactive form. This study is the first to suggest that the GPER pathway might regulate HSL activation in adipocytes.