## 4 Discussion  
The current study investigated the possible anti-diabetic and hypolipidemic potential of newly isolated Bulgarian autochthonous _L. paracasei_ strains in mature 3T3-L1 adipocytes. The obtained data indicated typical fat overload and an abrupt increase in lipolysis rate in MRS_C, compared to the non-induced control group. It was presumed that the applied eight days of adipogenic differentiation successfully mimicked the obesity-related enhanced systematic flux of FFA, which is generally accepted as a critical factor in the pathogenesis of muscle and liver insulin resistance and the lipotoxicity of peripheral tissues [49; 50]. Under these circumstances, we tested CFSs from _L. paracasei_ strains M2.1, C8, C15, and P4 at a dose of 10 percent for 48 h.  
Several studies have demonstrated that the administration of lactic acid bacteria to 3T3-L1 preadipocytes inhibits the early stages of adipogenesis by suppressing adipogenic transcriptional factors, such as PPAR\({}_{7}\), CCAAT-enhancer-binding proteins, fatty acid synthase, and fatty-acid-binding protein 4, and often potentiates glucose uptake [14; 18; 21; 22; 23]. The health benefits of these probiotics are more concerned with obesity prevention rather than treatment. The anti-obesity and anti-diabetic properties of probiotics are rarely explored in already mature adipocytes. [PERSON] et al. [51] conducted a parallel investigation of the _Lactobacillus gasseri_ LA39 bacterial product's effect on differentiating and already differentiated 3T3-L1 cells. Interestingly, the adipogenic differentiation was suppressed in the treated preadipocytes but not in the mature adipocytes. In another trial, [PERSON] et al. [20] tested the possible anti-obesity effect of the well-known probiotic strains of Lactobacillus _acidophilus_ and a cocktail of _Lactobacillus delbruckei_ sp. _Bulgaricus_ and _Streptococcus thermophilus_ in fully differentiated 3T3-L1 and established that both treatments suppressed lipid accumulation by the downregulation of crucial adipogenesis factors. Notably, the authors assumed that the aforementioned effect was due to the reduced entry and intracellular transport of lipids, which could be detrimental in vivo. Based on elevated blood lipid levels, the infiltration of lipids into non-lipidemic organs and subsequent cardiovascular disturbances are frequently observed, especially in overweight individuals exposed to factors highly predisposing to obesity. Contrarily, our results revealed that the tested M2.1, C8, C15 and P4 _L. paracasei_ strains enhanced the so-called \"buffer capacity\" of mature adipocytes due to the established increased glucose uptake, suppressed or unchanged lipolysis rate, and preserved intracellular lipid accumulation levels. Upon excess food intake or obesity-predisposing factors, such as immobilization and hormonal imbalances, a higher adipose tissue buffering capacity would maintain glucose and lipid homeostasis in physiological ranges over an extended period of time. Hence, the changes induced in this experiment would benefit the health status of obese individuals. Insulin signaling modulation plays a crucial role in storing excessive nutrients in adipose tissue by regulating the glucose influx, intracellular triglyceride synthesis, breakdown, deposition, and lipolysis rate and ultimately affecting the whole body's metabolism. Cellular mechanisms that modify physiological responses to insulin have been studied extensively, and multiple transduction pathways have been identified [4]. The IRS-1/PI3K/AKT pathway is assumed to be fundamental, mediated primarily by kinases counter-regulated by phosphatases (i.e., PI3K and PTEN) [52]. Regardless of the specific intracellular mechanism, increased insulin sensitivity in adipocytes provokes the translocation of insulin-induced glucose transporter 4 (GLUT4) from cytoplasmic storage vesicles to the cell membrane without changing the GLUT4-specific activity, followed by dramatically increasing the glucose flux rate into a cell.