title: Turbo methanol extract inhibits bone resorption through regulation of T cell function.
abstract: Marine organisms have bioactive potential which has tremendous pharmaceutical promise. Emerging evidence highlights the importance of the interplay between bone and the immune system of which T lymphocytes and their product act as key regulators of bone resorption. In the present investigation we have analyzed the anti-osteoporotic effect of turbo methanol extract (TME) in the reversal of bone resoprtion. Forty-two female Swiss albino mice were used and randomly assigned into sham-operated group (sham) and six ovariectomized (OVX) subgroups, i.e. OVX with vehicle (OVX) that received daily oral administration of water ad libitum; OVX with estradiol (2mg/kg/day); and OVX with different doses of TME i.e. TME 100mg/kg, TME 50mg/kg, TME 25mg/kg and TME 12.5mg/kg. Oral administration of TME or estradiol started on the second week after ovariectomy for a period of 4weeks. We observed that the administration of TME increased the trabeculation in tibia and reduced the atrophy in the uterus. TME significantly decreased the serum alkaline phosphatase (ALP) and acid phosphatase (ACP) activity in OVX mice. Micro CT analysis revealed that the TME administration preserved the bone volume, connectivity density, trabecular number, trabecular thickness and trabecular separation in OVX mice. Bone mineralization was measured in different groups of mice by Raman spectroscopy. Reversal of bone resorption was observed in TME treated group of mice. To further investigate the mechanism of action of TME, we analyzed the T lymphocyte proliferation and profiles of cytokine TNFα and sRANKL in TME treated ovariectomized mice. Decrease in the elevation of T cell subsets was observed after the supplementation with TME. The extract significantly lowered the T cell proliferation responses to mitogens, phorbol 12-myristate 13-acetate (PMA) and ionomycin (Io) and phytohemagglutinin (PHA). A marked reduction in TNFα and sRANKL secretion in serum and TNFα in cell free supernatants of activated T lymphocytes was observed upon TME administration. TME could significantly inhibit the in vitro osteoclastogenesis and the bone resorption observed using artificial calcium coated slides. Collectively, these results indicate that TME has the potential to inhibit bone resorption and may prove to be a potential candidate for the development of an anti-osteoporosis drug.
authors.affiliation: Department of Zoology, The D. G. Ruparel College, Mahim, Mumbai 40016, India.
authors.forename: Babita
authors.initials: B
authors.lastname: Balakrishnan
authors.forename: Madhavi M
authors.initials: MM
authors.lastname: Indap
authors.forename: Surya P
authors.initials: SP
authors.lastname: Singh
authors.forename: C Murali
authors.initials: CM
authors.lastname: Krishna
authors.forename: Shubhada V
authors.initials: SV
authors.lastname: Chiplunkar
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D000469:Alkaline Phosphatase / Q000097:blood; D000818:Animals; D015415:Biomarkers / Q000097:blood; D001862:Bone Resorption / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000276:immunology*; D002113:Calcification, Physiologic / Q000187:drug effects; D002118:Calcium / Q000097:blood; D049109:Cell Proliferation / Q000187:drug effects; D045424:Complex Mixtures / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D016131:Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology; D000432:Methanol / Q000737:chemistry*; D051379:Mice; D008934:Mitogens / Q000494:pharmacology; D008974:Mollusca / Q000737:chemistry*; D010010:Osteoclasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects; D010052:Ovariectomy; D053245:RANK Ligand / Q000097:blood; D013059:Spectrum Analysis, Raman; D013154:Spleen / Q000187:drug effects / Q000473:pathology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013977:Tibia / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D014599:Uterus / Q000187:drug effects / Q000473:pathology; D055114:X-Ray Microtomography
chemical_list: D015415:Biomarkers; D045424:Complex Mixtures; D008934:Mitogens; D053245:RANK Ligand; D014409:Tumor Necrosis Factor-alpha; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D002118:Calcium; D000432:Methanol
keywords: ACP; ALP; Bone resorption; ERT; FBS; Io; M-CSF; OC; OVX; Osteoclastogenesis; Osteoporosis; PHA; PMA; RANKL; Raman spectroscopy; TME; TNFα; Turbo methanol extract; acid phosphatase; alkaline phosphatase; estrogen replacement therapy; fetal bovine serum; ionomycin; macrophage-colony stimulating factor; osteoclast; ovariectomized mice; phorbol 12-myristate 13-acetate; phytohemagglutinin; receptor activator of nuclear factor kappa-B ligand; sRANKL; soluble RANKL; tumor necrosis factor α; turbo methanol extract; α-MEM; α-minimum essential medium