Table 2.

In vitro studies on human samples evaluating the beneficial effects of BT on immune response in musculoskeletal diseases

Authors		Journal		Pathology		Experimental model			Treatment		Mineral water or inorganic or organic components			Biochemicalparameters	Results
Fox et al. 2012 [13]		J Cell Mol Med		RA		Human primary articular chondrocytes			IL-1β, IL-6 and TNF-α (5 ng/mL) for 6, 12 and 18 h + GYY4137 (50–500 mol/L) dissolved in the culture medium, for 12 h		GYY4137			Cell death; Mitochondrial membrane potential	↓ cell death and oxidant-induced mitochondrial dysfunction ↓ inflammation
Li et al. 2013 [14]		J Cell Mol Med		RA		Human primary arthritis synoviocytes and chondrocytes			(0.1–0.5 mM) dissolved in the culture medium, for 18 h + LPS (10 μg/mL)		GYY4137				↓ IL-6, TNF-α, PGE2 and NO production ↓ COX-2 and iNOS catalytic activity ↓ NF-kB activation ↓ inflammatory processes
Burguera et al. 2014 [15]		Osteoarthr Cartil		OA		Human primary OA chondrocytes			NaHS and GYY4137 (0.05–1 mM) dissolved in the culture medium, for 24 or 48 h + IL-1β (5 ng/mL)		NaHS and GYY4137			IL-6, PGE2, PTGES, COX-2; NO, NOS2; MMP-13; NF-kB signaling activation	↓ IL-6, PGE2, and NO release and protein level ↓ IL-6, PTGES, COX-2, and NOS2 gene expression ↓ NF-κB nuclear translocation ↓ inflammatory and degrading processes
Ha et al. 2015 [16]		Int J MolMed		OA		Human primary OA chondrocytes			NaHS (0.06–1.5 mM) dissolved in the culture medium, for 24 h + IL-1β (10 ng/mL)		NaHS			COX-2, iNOS, MMP-13; ERK/IκBα/NF-κB signaling activation	↓ COX-2, iNOS, MMP-13 release and gene expression ↓ERK/IκBα/NF-κB activation ↓ degrading processes
Sieghart et al. 2015 [18]		J Cell Mol Med				Human primary OA fibroblast-like synoviocytes			NaHS (0.06–1 mmol/L) dissolved in the culture medium, for 1 h + IL-1β (10 ng/mL)		NaHS			IL-6, IL-8; MMP-2, MMP-14; MAPK and Akt1/2/PI3K protein phosphorylation	↓ IL-6 and IL-8 secretion, MMP-2 and MMP-14 gene expression ↓ MAPK phosphorylation ↑ Akt1/2 phosphorylation ↓ inflammatory and degrading processes
Vela-Anero et al. 2017 [19]		Nitric Oxide		OA		Human OA cartilage disks			NaHS or GYY4137 (200 or 1000 μM) dissolved in the culture medium, for 21 days + IL-1β (5 ng/mL)		NaHS and GYY4137			MMP-3, MMP-13; COL2A1, glycosaminoglycans, aggrecans	↓ MMP-3 and MMP-13 production ↑ COL2A1, glycosaminoglycans and aggrecans synthesis ↓ degrading processes
Fioravanti et al. 2013 [17]		J Biol Regul Homeost Agents		OA		Human primary OA chondrocytes			25%, 50%, or 100% of Vetriolo thermal water dissolved in the culture medium, for 48 h + IL-1β (5 ng/mL)		Vetriolo thermal water (Trentino Alto Adige Italy), strongly acidic sulfate, rich in calcium, magnesium and iron			NO, iNOS; Cell viability and apoptosis; Morphological assessment	25%, 50% of Vetriolo water ↑ survival recovery rate ↓ NO levels, iNOS expressions, and apoptosis ↑ morphological characteristics ↓ degrading processes
Kloesch et al. 2010 [20]	Cell Biol Int			RA	fibroblast-like synoviocytes			NaHS (200 mM)		NaHS			IL-6; activation/deactivation of MAPKs; p38 and p44/42 MAPK (ERK1/2)		↓ IL-1β-induced expression of IL-6 with low concentrations of NaHS H2S deactivates p44/42 MAPK (ERK1/2) ↑ activation of p38 MAPK, ERK1/2 and IL-6 with long-term exposure to H2S
Kloesch et al. 2012 [21]	Immunol Lett		RA and OA		RA and OA human fibroblast- like synoviocytes		NaHS (1.0 mM) dissolved in the culture medium, for 1, 3, 6, 12 h			NaHS		IL-6, IL-8, COX-2; MMP-2, MMP-3, MMP-14; p38/MAPK/ERK protein expression			↑ IL-6, IL-8, COX-2 and p38/MAPK/ERK expression
Kloesch et al. 2012 [22]	Rheumatol Int		RA		Human chondrocyte cell line		NaHS (0.125 and 1.0 mM) dissolved in the culture medium, for 15, 30, 45 and 60 min + MAPK inhibitors (1 and 5 μM) + IL-1β(5 ng/mL) for 1 h			NaHS		IL-6, IL-8; P38/MAPK/ERK and NF-kB signaling activation/- deactivation			↓ IL-6 and IL-8 ↓ p38/MAPK/ERK ↓ NF-kB signalling ↓ inflammatory processes
Gambari et al. 2014 [23]		Pharmacol Res		Osteoporosis		Human differentiated osteoclasts			NaHS (50–300 μM) dissolved in the culture medium, for 72 h to 6 days		NaHS			Osteoclasts differentiation; ROS production, NRF2, KEAP1, NQO1, and PRDX1	↓ osteoclast differentiation ↓ intracellular ROS levels ↑ NRF2 protein expression and nuclear translocation ↑ antioxidant gene

Akt protein-chinasi B, COL2A1 collagen type II alpha 1 chain, COX cyclooxygenase, ERK extracellular signal-regulated kinase, GYY4137 morpholin-4-ium 4 methoxyphenyl (morpholino) phosphinodithioate, IκBα inhibitor of nuclear factor kappa B, IL interleukin, iNOS inducible nitric oxide synthase, KEAP1 kelch like ECH associated protein 1, LPS lipopolysaccharide, MAPK mitogen-activated protein kinase, MMP matrix metalloproteinase, NaHS sodium hydrosulfide, NF-kB nuclear factor kappa B, NO nitric oxide, NOS2 nitric oxide synthase 2, NQO1 NAD(P)H quinone dehydrogenase 1, NRF2 nuclear factor-erythroid factor 2-related factor 2, OA osteoarthritis, PGE2 prostaglandin E2, PI3K phosphoinositide 3-kinase, PRDX1 peroxiredoxin 1, PTGES prostaglandin E synthase, RA rheumatoid arthritis, ROS reactive oxygen species, TNF tumor necrosis factor, ↓ decrease, ↑ increase