Staphylococcus epidermidis SAS1: new probiotic candidate for obesity and allergy treatment their mechanistic insights and cytotoxicity evaluation

Abstract

Background: Probiotics are live bacteria that provides numerous healthy and beneficial effects to the consumers. The present study aimed to investigate the effect of a probiotic candidate Staphylococcus epidermidis SAS1, in immunoregulation and obesity management.

Methods: : This probiotic candidate was isolated from a soil sample collected from a region of fruit waste decomposition. In vitro cytotoxicity was assessed using the THP-1 (human leukemia monocytic cell line) cells using MTT assay.

Results: An IC50 value of 47.52 ± 0.18 μg/mL and cell shrinkage were observed along with the release of cellular content of THP-1 cells. The higher production of reactive oxygen species and lesser release of interleukins (IL-4, 5, and 13) are attributed to the antiallergic potential of this strain. Furthermore, in vitro cytotoxicity evaluation using 3T3-L1 cells identified this strain as a promising candidate for anti-obesity treatment. The observed IC50 value was 514.4 ± 0.061 μg/mL.

Discussion: This extract was shown to have good lipase-inhibiting enzyme activity and was reported to prevent adipogenesis, depicted by increased HDL levels and decreased LDL and triglyceride levels. These results suggested that Staphylococcus epidermidis SAS1 may have therapeutic use in the treatment of obesity and allergies.

Keywords: Staphylococcus epidermidis; allergy; obesity; probiotic candidate; therapeutic treatment.

Figure 1

(a) Reduction in the number of THP-1 cell line on increasing the exposure of S. epidermidis SAS1 bioactive metabolites; (b) Flow cytometry % DCFDA stained cells; (c) Medium fluorescence intensity (MFI) of reactive oxygen species (ROS). The data represents mean n = 3 ± SD. Mean with different superscript letters are different by Tukey’s post hoc test (p < 0.05).

Figure 2

(a) Morphology of control THP-1 cells; morphological changes in THP-1 cells on treatment with (b) 1 μg/mL; (c) 10 μg/mL; (d) 50 μg/mL; (e) 100 μg/mL; (f) 250 μg/mL; (g) 500 μg/mL; (h) 1,000 μg/mL concentration of S. epidermidis SAS1 bioactive metabolites. Normal live cells are indicated by black arrowheads and dead cells and apoptotic cells with indicated by orange arrowheads.

Figure 3

Flow cytometry plots for apoptosis detection in (a) Unstained, (b) Control and (c) S. epidermidis SAS1 treated cells.

Figure 4

Downregulation of the cytokine at IC₅₀ dose of SAS bioactive metabolites (a) IL-4; (b) IL-5; (c) IL-13; (d) Percentage lipase inhibition activity of SAS1 bioactive metabolites. (e) Glyceride: LDL cholesterol measurement. (f) Glyceride: HDL cholesterol measurement. The data represents mean n = 3 ± SD. Mean with different superscript letters are different by Tukey’s post hoc test (p < 0.05).

Figure 5

Reduction in the number of viable 3T3 L1 on increasing the exposure of S. epidermidis SAS1 bioactive metabolites. The data represents mean n = 3 ± SD. Mean with different superscript letters are different by Tukey’s post hoc test (p < 0.05).

Figure 6

(a) Morphology of control 3T3 L1 cells; morphological changes in 3T3 L1 cells on treatment with (b) 1 μg/mL; (c) 10 μg/mL; (d) 50 μg/mL; (e) 100 μg/mL; (f) 250 μg/mL; (g) 500 μg/mL; (h) 1,000 μg/mL concentration of S. epidermidis SAS1 bioactive metabolites. Normal live cells are indicated by black arrowheads and apoptotic damage and release of their content is indicated by yellow arrowheads.

Figure 7

Measurement of triglyceride content. The data represents mean n = 3 ± SD.