Smoking during pregnancy increases chemerin expression in neonatal tissue

Chemerin triggers migration of a CD8 T cell subset with natural killer cell functions

The recruitment of cells with effector functions into the tumor microenvironment holds potential for delaying cancer progression. We show that subsets of human CD28-effector CD8 T cells, CCR7- CD45RO+ effector memory, and CCR7- CD45RO- effector memory RA phenotypes, express the chemerin receptor CMKLR1 and bind chemerin via the receptor. CMKLR1-expressing human CD8 effector memory T cells present gene, protein, and cytotoxic features of NK cells. Active chemerin promotes chemotaxis of CMKLR1-expressing CD8 effector memory cells and triggers activation of the α4β1 integrin. In an experimental prostate tumor mouse model, chemerin expression is downregulated in the tumor microenvironment, which is associated with few tumor-infiltrating CD8+ T cells, while forced overexpression of chemerin by mouse prostate cancer cells leads to an accumulation of intra-tumor CD8+ T cells. Furthermore, α4 integrin blockade abrogated the chemerin-dependent recruitment of CD8+ T effector memory cells into implanted prostate tumors in vivo. The results identify a role for chemerin:CMKLR1 in defining a specialized NK-like CD8 T cell, and suggest the use of chemerin-dependent modalities to target effector CMKLR1-expressing T cells to the tumor microenvironment for immunotherapeutic purposes.

Physical activity during pregnancy alters gene expression in neonatal tissue

Reducing the risk of developing chronic disease, such as obesity and type 2 diabetes, is an important component of successful aging. Offspring born to mothers who exercise during pregnancy have improved body composition and metabolic profiles. However, mechanisms to explain this phenomenon are lacking.

Purpose

This study examined whether maternal step counts were correlated with neonatal gene expression markers related to glucose metabolism and adipogenesis.

Methods

Physical activity levels were assessed in women with male neonates via Fitbit Flex® during the second and third trimester of pregnancy. The dartos and epidermal/dermal layers of the foreskin were collected following circumcision in full-term, singleton, neonates (n = 12 dartos and n = 14 dermal). Tissue was homogenized, RNA isolated, and a NanoString code set was run to quantify a panel of genes related to glucose metabolism and adipogenesis.

Results

Twelve genes were correlated to steps per day with a P-value of <0.05. After adjusting for multiple comparisons, six genes remained significantly correlated to steps per day (False Discovery Rate-corrected P-value < 0.10). Notably, glucose transporter 1, adiponectin receptor 1, and CCAAT/enhancer-binding protein alpha and beta were positively correlated with steps per day, while peroxisome proliferator-activated receptor alpha and peroxisome proliferator-activated receptor gamma coactivator 1- alpha were negatively correlated with steps per day.

Conclusion

Maternal physical activity is associated with offspring gene expression markers of adipogenesis, insulin sensitivity and glucose uptake. Future studies should aim to mechanistically examine whether these markers are driving increased adiposity in offspring born to sedentary mothers.

The Role of the Adipokines in the Most Common Gestational Complications

Adipocytokines are hormonally active molecules that are believed to play a key role in the regulation of crucial biological processes in the human body. Numerous experimental studies established significant alterations in the adipokine secretion patterns throughout pregnancy. The exact etiology of various gestational complications, such as gestational diabetes, preeclampsia, and fetal growth abnormalities, needs to be fully elucidated. The discovery of adipokines raised questions about their potential contribution to the molecular pathophysiology of those diseases. Multiple studies analyzed their local mRNA expression and circulating protein levels. However, most studies report conflicting results. Several adipokines such as leptin, resistin, irisin, apelin, chemerin, and omentin were proposed as potential novel early markers of heterogeneous gestational complications. The inclusion of the adipokines in the standard predictive multifactorial models could improve their prognostic values. Nonetheless, their independent diagnostic value is mostly insufficient to be implemented into standard clinical practice. Routine assessments of adipokine levels during pregnancy are not recommended in the management of both normal and complicated pregnancies. Based on the animal models (e.g., apelin and its receptors in the rodent preeclampsia models), future implementation of adipokines and their receptors as new therapeutic targets appears promising but requires further validation in humans.

Chemerin Is Induced in Non-Alcoholic Fatty Liver Disease and Hepatitis B-Related Hepatocellular Carcinoma

Chemerin is protective in experimental models of hepatocellular carcinoma (HCC). Noteworthy, chemerin mRNA and protein were reduced in HCC tissues of Asian patients with mostly hepatitis B disease etiology. The current study nevertheless showed that chemerin protein was induced in tumor tissues of European HCC patients with non-alcoholic fatty liver disease (NAFLD) and patients with unclear disease etiology. A similar regulation was observed in hepatitis B virus (HBV), but not in hepatitis C virus (HCV), related HCC. The apparent discrepancy between the regulation of chemerin in HBV-HCC obtained from our study and recent reports led us to use the chemerin antibodies applied in the previous assays. These antibodies could not equally detect different chemerin isoforms, which were overexpressed in HepG2 cells. Higher chemerin protein in HCC was nevertheless confirmed by the use of all antibodies. Chemerin protein was low in Huh7 and PLC/PRF/5 cells whereas HepG2 and Hep3B cells had chemerin protein similar as primary human hepatocytes. Besides, the anti-tumor effects of retinoids in hepatocyte cell lines did not enclose upregulation of chemerin, which was initially discovered as a tazarotene induced protein in the skin. Finally, protein levels of the chemerin receptor, chemokine-like receptor 1 (CMKLR1), declined in non-viral, and tended to be lower in HBV-HCC tissues suggesting reduced chemerin activity in the tumors. To sum up, our work showed an opposite regulation of chemerin and CMKLR1 in NAFLD and HBV associated HCC. In HCV-HCC neither chemerin nor its receptor were changed in the tumor tissues. Current findings do not support a critical role of total chemerin protein levels in HCC of non-viral and viral etiology. Accordingly, tumor-localized chemerin protein was not associated with tumor-node-metastasis classification.