Lotus leaf extract and L-carnitine influence different processes during the adipocyte life cycle

Abstract

BackgroundThe cellular and molecular mechanisms of adipose tissue biology have been studied extensively over the last two decades. Adipose tissue growth involves both an increase in fat cell size and the formation of mature adipocytes from precursor cells. To investigate how natural substances influence these two processes, we examined the effects of lotus leaf extract (Nelumbo nucifera-extract solution obtained from Silab, France) and L-carnitine on human preadipocytes and adipocytes.MethodsFor our in vitro studies, we used a lotus leaf extract solution alone or in combination with L-carnitine. Utilizing cultured human preadipocytes, we investigated lotus leaf extract solution-induced inhibition of triglyceride incorporation during adipogenesis and possible effects on cell viability. Studies on human adipocytes were performed aiming to elucidate the efficacy of lotus leaf extract solution to stimulate lipolytic activity. To further characterize lotus leaf extract solution-mediated effects, we determined the expression of the transcription factor adipocyte determination and differentiation factor 1 (ADD1/SREBP-1c) on the RNA- and protein level utilizing qRT-PCR and immunofluorescence analysis. Additionally, the effect of L-carnitine on beta-oxidation was analyzed using human preadipocytes and mature adipocytes. Finally, we investigated additive effects of a combination of lotus leaf extract solution and L-carnitine on triglyceride accumulation during preadipocyte/adipocyte differentiation.ResultsOur data showed that incubation of preadipocytes with lotus leaf extract solution significantly decreased triglyceride accumulation during adipogenesis without affecting cell viability. Compared to controls, adipocytes incubated with lotus leaf extract solution exhibited a significant increase in lipolysis-activity. Moreover, cell populations cultivated in the presence of lotus leaf extract solution showed a decrease in adipocyte differentiation capacity as indicated by a decrease in the ADD1/SREBP-1c signal. Importantly, our results demonstrated that a combination of lotus leaf extract solution and L-carnitine reduced triglyceride accumulation to a greater extent compared to incubation with either substance alone.ConclusionsOverall, our data demonstrate that a combination of lotus leaf extract and L-carnitine reduced triglyceride accumulation in human (pre)adipocytes by affecting different processes during the adipocyte life cycle. For this reason, this combination might represent a treatment option for obesity-related diseases.

Propionyl-L-carnitine Corrects Metabolic and Cardiovascular Alterations in Diet-Induced Obese Mice and Improves Liver Respiratory Chain Activity

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Topically applied l‐carnitine effectively reduces sebum secretion in human skin

“…In the mouse 3T3‐L1 cell line, it was shown that l ‐carnitine stimulates lipolysis‐activity and increases the expression of genes involved in β‐oxidation 15 . In human adipocytes, a significantly augmented β‐oxidation was demonstrated in cultured human primary preadipocytes as well as differentiated adipocytes after incubation with l ‐carnitine, compared to control cells 16 …”

Co‐administration of nuciferine reduces the concentration of metformin in liver via differential inhibition of hepatic drug transporter OCT1 and MATE1

“…Folium Nelumbinis, dried leaves of Nelumbo nucifera Gaertn, possesses various pharmacological activities, such as antioxidant (Lin, Kuo, Lin, & Chiang, ) and immunomodulatory (Liu et al, ), and has been extensively applied as a traditional Chinese medicine, tea and food supplements (Du et al, ; Mukherjee, Mukherjee, Maji, Rai, & Heinrich, ). Recent pharmacological studies demonstrated that Folium Nelumbinis also had an anti‐obesity effect by inhibiting the absorption of lipids and carbohydrates, accelerating lipid metabolism, and reducing triglyceride accumulation in adipocytes (Ahn et al, ; Du et al, ; Siegner et al, ). Thus, Folium Nelumbinis is used as a health food or as a Chinese traditional medicine (TCM) in elderly populations with hyperlipemia for the regulation of glucose and lipid metabolism, and the lipid‐lowering effect is supposed to be attributed to nuciferine (NF, Figure ).…”