Peritumoral adipose tissue promotes lipolysis and white adipocytes browning by paracrine action

The Different Shades of Thermogenic Adipose Tissue

PURPOSE OF REVIEW

By providing a concise overview of adipose tissue types, elucidating the regulation of adipose thermogenic capacity in both physiological contexts and chronic wasting diseases (a protracted hypermetabolic state that precipitates sustained catabolism and consequent progressive corporeal atrophy), and most importantly, delving into the ongoing discourse regarding the role of adipose tissue thermogenic activation in chronic wasting diseases, this review aims to provide researchers with a comprehensive understanding of the field.

RECENT FINDINGS

Adipose tissue, traditionally classified as white, brown, and beige (brite) based on its thermogenic activity and potential, is intricately regulated by complex mechanisms in response to exercise or cold exposure. This regulation is adipose depot-specific and dependent on the duration of exposure. Excessive thermogenic activation of adipose tissue has been observed in chronic wasting diseases and has been considered a pathological factor that accelerates disease progression. However, this conclusion may be confounded by the detrimental effects of excessive lipolysis. Recent research also suggests that such activation may play a beneficial role in the early stages of chronic wasting disease and provide potential therapeutic effects. A more comprehensive understanding of the changes in adipose tissue thermogenesis under physiological and pathological conditions, as well as the underlying regulatory mechanisms, is essential for the development of novel interventions to improve health and prevent disease.

Prognostic value of preoperative radiographic perinephric fat features in renal cell carcinoma patients undergoing surgery

BACKGROUND

We aimed to assess the prognostic importance of perinephric fat features in images of patients with non-metastatic renal cell carcinoma (RCC) undergoing surgery.

METHODS

We enrolled RCC patients who underwent surgical treatment between 2011 and 2019. Two characteristics, including perinephric fat thickness and perinephric fat stranding, were evaluated using preoperative computed tomography or magnetic resonance images. The association between perinephric fat characteristics and disease progression was examined by Kaplan-Meier survival analysis and Cox regression model.

RESULTS

In a multivariate Cox proportional hazards model adjusting for tumor stage, intratumoral necrosis, and neutrophil-to-lymphocyte ratio, we found that patients in the thin perinephric fat group (<1 cm) had a poorer progression-free survival (PFS) compared to the thick perinephric fat group (≥1 cm) (HR 2.8; 95% CI 1.175-6.674, p = 0.02). Additionally, the fat stranding group had a poorer PFS than the non-stranding group (HR 3.852; 95% CI 1.082-13.704, p = 0.037). The non-stranding with thick perinephric fat group exhibits the highest cumulative PFS while the stranding with thin perinephric fat group has the lowest cumulative PFS. In receiver operating characteristic curve analysis, combing these two perinephric fat characteristics with tumor stage can achieve a better discriminatory power than tumor stage alone.

CONCLUSIONS

Our study indicates that the evaluation of image-based perinephric fat features is a simple, straightforward, reproducible tool for predicting RCC prognosis and may assist in preoperative risk stratification.

The Role of Cancer Stem Cell Markers in Ovarian Cancer

Ovarian cancer is the most lethal gynaecological cancer and the eighth most common female cancer. The early diagnosis of ovarian cancer remains a clinical problem despite the significant development of technology. Nearly 70% of patients with ovarian cancer are diagnosed with stages III-IV metastatic disease. Reliable diagnostic and prognostic biomarkers are currently lacking. Ovarian cancer recurrence and resistance to chemotherapy pose vital problems and translate into poor outcomes. Cancer stem cells appear to be responsible for tumour recurrence resulting from chemotherapeutic resistance. These cells are also crucial for tumour initiation due to the ability to self-renew, differentiate, avoid immune destruction, and promote inflammation and angiogenesis. Studies have confirmed an association between CSC occurrence and resistance to chemotherapy, subsequent metastases, and cancer relapses. Therefore, the elimination of CSCs appears important for overcoming drug resistance and improving prognoses. This review focuses on the expression of selected ovarian CSC markers, including CD133, CD44, CD24, CD117, and aldehyde dehydrogenase 1, which show potential prognostic significance. Some markers expressed on the surface of CSCs correlate with clinical features and can be used for the diagnosis and prognosis of ovarian cancer. However, due to the heterogeneity and plasticity of CSCs, the determination of specific CSC phenotypes is difficult.

Dietary Apigenin Relieves Body Weight and Glycolipid Metabolic Disturbance via Pro-Browning of White Adipose Mediated by Autophagy Inhibition

SCOPE

Apigenin (AP) has many pharmacological activities, including anti-inflammation, hyperlipidemia-lowering, and so on. Previous studies show that AP can reduce lipid accumulation in adipocytes in vitro. However, it remains unclear whether and how AP can promote fat-browning. Therefore, mouse obesity model and preadipocyte induction model in vitro are used to investigate the effects of AP on glycolipid metabolism, browning and autophagy as well as the possible mechanisms.

METHODS AND RESULTS

The obese mice are intragastrically administrated with AP (0.1 mg g-1  d-1 ) for 4 weeks; meanwhile, the differentiating preadipocytes are respectively treated with the indicated concentrations of AP for 48 h. Metabolic phenotype, lipid accumulation, and fat-browning are respectively evaluated by morphological, functional, and specific markers analysis. The results show that AP treatment alleviates the body weight, glycolipid metabolic disorder, and insulin resistance in the obese mice , which is contributed to the pro-browning effects of AP in vivo and in vitro. Moreover, the study finds that the pro-browning effect of AP is accomplished through autophagy inhibition mediated by the activation of PI3K-Akt-mTOR pathway.

CONCLUSIONS

The findings highlight that autophagy inhibition promotes the browning of white adipocytes and suggest that AP would prevent and treat obesity and the associated metabolic disorders.