Vitamin A and its metabolites are key regulators of the development of adipose tissue and associated metabolic complications. The aim of this study was to determine the effect of high fat diet and 13-cis retinoic acid (13 cRA) application on metabolic parameters, adipogenic and inflammatory indicators in female Lewis rats. Female rats of Lewis strain were fed standard laboratory diet (STD) and high fat diet (HFD, 45% of saturated fatty acids) during 30 days. The groups were divided into additional 3 groups (6 rats each): two experimental groups that received 13 cRA orally on a daily basis during 30 days (7.5 mg/kg and 15 mg/kg, respectively) and the control group that was given sunflower oil. Animals were sacrificed after 60 days. Feeding of Lewis rats with chronic HFD diet with 13 cRA supplementation increased weight gain, adiposity index, dyslipidaemia, hyperleptinaemia, insulin resistance, VLDL concentrations, oxidative stress and atherogenic indices. Administration of 13 cRA in Lewis rats fed STD did not change the weight of the animals, but it slightly increased the atherogenic parameters. 13 cRA and HFD affect metabolic parameters, glucose and lipid metabolism in Lewis rats and its administration has a completely different effect on metabolism in rats fed STD, highlighting the complex role of vitamin A supplementation in obesity. Other factors, such as genetics, age, sex, adipose tissue distribution, also must be taken into consideration.

Childhood obesity is a complex health problem, and not many studies have been done on adipose tissue remodeling in early childhood. The aim of this study was to examine extracellular matrix remodeling in the adipose tissue of healthy male children depending on their weight status. Subcutaneous and visceral adipose tissue was obtained from 45 otherwise healthy male children who underwent elective surgery for hernia repairs or orchidopexy. The children were divided into overweight/obese (n = 17) or normal weight groups (n = 28) depending on their body mass index (BMI) z-score. Serum was obtained for glucose, testosterone, triglyceride, total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) measurements. Sections of adipose tissue were stained with hematoxylin and eosin to determine the adipocytes’ surface area, and Masson’s trichrome stain was used to detect the adipocytes’ collagen content. Immunohistochemistry for CD163⁺ cells was also performed. The results showed that male children in the overweight group had higher serum triglyceride levels, greater adipocyte surface area and collagen content in their subcutaneous adipose tissue, more crown-like structures in fat tissues, and more CD163⁺ cells in their visceral adipose tissue than males in the normal weight group. In conclusion, in male children, obesity can lead to the hypertrophy of adipocytes, increased collagen deposition in subcutaneous adipose tissues, and changes in the polarization and accumulation of macrophages.

Background and Objectives: The extracellular matrix is important for adipose tissue growth, and numerous interactions between adipocytes and extracellular matrix components occur during adipose tissue development. The main objective of this study was to investigate the interaction and influence of maternal and postnatal diet on adipose tissue remodeling in Sprague Dawley offspring. Materials and Methods: 10 Sprague Dawley females were randomly divided into two groups at nine weeks of age and fed a standard laboratory diet or high-fat diet for six weeks. Then, they were mated, and after birth, their male rat offspring were divided into four subgroups according to diet. After euthanizing the offspring at 22 weeks of age, samples of subcutaneous, perirenal and epididymal adipose tissue were collected. Sections were stained with Mallory’s trichrome and analyzed by immunohistochemistry for CD68⁺ and CD163⁺ cells. Results: Staining of extracellular components showed higher collagen deposition in the perirenal and epididymal depot of offspring fed a high-fat diet. The number of CD163/CD68⁺ cells in the perirenal adipose tissue was lower in the CD-HFD group compared with other groups, and in the subcutaneous fat pad when the groups with modified diet were compared with those on non-modified diet. Conclusion: Morphological changes in adipose tissue, increased collagen deposition, and changes in macrophage polarization may be related to intergenerational changes in diet.

Background and Objectives: A high-fat diet causes inflammation in the organism and many metabolic disorders. Adipose tissue secretes adipokines that affect the function of many organs. The health status of the mother before and during pregnancy affects the health of the offspring. The aim of this study was to determine how the type of maternal diet and the change in the type of diet in the offspring affects the histological characteristics of the ovaries and subcutaneous and perigonadal adipose tissue in female rat offspring. Materials and Methods: Ten female rats were divided into two groups. One group was fed standard laboratory chow, and the other was fed a high-fat diet and mated with a male of the same breed. The offspring of both groups of dams were divided into four subgroups with different feeding protocols. At 22 weeks of age, the offspring were sacrificed. Ovaries and subcutaneous and perigonadal adipose tissue were isolated. In the ovaries, the presence of cystic formations was investigated. Histomorphometric analysis was performed in two types of adipose tissue. Results: The weight of the ovaries of the offspring of mothers fed a high-fat diet was significantly higher than that of the offspring of mothers fed standard laboratory diets. Cystic formations were found in the ovaries of the offspring of mothers fed a high-fat diet. In subcutaneous adipose tissue, the percentage of small-sized adipocytes was significantly higher in the offspring of mothers fed standard laboratory diets. There were no significant differences in adipocyte surface area and adipocyte number between groups. Conclusion: Maternal diet influences the morphology of the ovaries and adipose tissue of the offspring.

Background/Objectives: Overweight and obesity in early childhood is a serious public health problem as in most cases it persists into adulthood and significantly affects the quality of life. The aim of this study was to investigate the mechanisms that trigger extracellular matrix (ECM) remodeling in the subcutaneous (SAT) and visceral (VAT) adipose tissue of male children in relation to their body weight. Methods: During elective abdominal surgery, SAT and VAT were acquired from 75 male subjects undergoing hernia repair (inguinal herniorrhaphy by Ferguson) or orchidopexy. Based on their Z-score, subjects were separated into two groups. The morphometry of both adipose tissue compartments was assessed after hematoxylin and eosin histological staining, immunohistochemistry to quantify CD163⁺ cells and the number of crown-like structures (CLSs), and real-time polymerase chain reaction to assess the relative gene expression for collagen VI subtype alpha 3 (COL6α3). Results: Obese and overweight individuals were found to have higher numbers of CD163⁺ cells, greater numbers of CLSs in VAT and SAT, and a higher expression of COL6α3 in both compartments. Conclusions: Obesity in childhood may lead to increased COL6α3 gene expression and promote the activation of macrophage polarization, compromise the structural integrity of the ECM, and thus influence the development of inflammatory processes.