haidut
Member
The activation of TLR by various substances like endotoxin, ethanol / alcohol, opioids, SSRI, etc is involved in the pathogenesis of many conditions, especially IBD, colon cancer, periodontal disease, etc. There are very few effective endotoxin antagonists in clinical use, which is unfortunate since they have the potential to treat a variety of serious systemic conditions. I posted about niacinamide and potentially riboflavin antagonizing the effects of endotoxin but as far as I know these vitamins are not true TLR "receptor" antagonist. Thus, while I was searching for such direct antagonists I stumbled upon a number of studies showing that vitamin D3 and its "activated" form calcitriol are both potent TLR4 antagonists, with proven clinical effects. Some of the studies below are human, and as you can see as little as 2,000 IU D3 daily prevented eclampsia in many women at risk for the condition. Higher doses in the range of 20,000 IU - 25,000 IU have the potential to treat even more serious conditions like colon cancer. What is amazing is that some of the studies identified profound TLR4 antagonism even from very small doses of about 500 IU vitamin D3 daily, especially when combined with pregnenolone / progesterone. One of the studies went as far as suggesting that vitamin D would be viable treatment for sepsis given how effective it is an antagonizing the effects of even large amounts of endotoxin.
Finally, even high doses vitamin D3 used in some of these studies did not cause hypercalcemia, so the most feared side effect of vitamin D is apparently not that common.
"...Consistent with these findings, our results showed that high-dose 1,25(OH)2D3 administration could significantly protect against liver inflammation and fibrosis in diabetic rats. However, some larger, randomized, placebo-controlled trials are required to detect the effects of vitamin D supplementation for the treatment of NAFLD and to determine the optimal levels of vitamin D. Furthermore, we found that the expression of TLR4, NF-κB, and TNF-α was downregulated by 1,25(OH)2D3 in a dose-dependent manner. We also observed differences in CD68 staining among groups, indicating changes in Kupffer cell/macrophage numbers. Many of the changes observed in the liver were secondary to the changes in Kupffer cell numbers, and these alterations may mediate the anti-inflammatory effects of high-dose 1,25(OH)2D3 in the liver of diabetic rats. Because high-dose 1,25(OH)2D3 may lead to problems such as hypercalcemia, we also tested serum calcium and phosphate levels. Our results showed that the levels of serum calcium and phosphate in rats treated with 1,25(OH)2D3 were not significantly different compared with those in normal rats."
Animal studies:
Vitamin D [1,25(OH)2D3] Differentially Regulates Human Innate Cytokine Responses to Bacterial versus Viral Pattern Recognition Receptor Stimuli. - PubMed - NCBI
Vitamin D inhibits lipopolysaccharide-induced inflammatory response potentially through the Toll-like receptor 4 signalling pathway in the intestin... - PubMed - NCBI
Progesterone and vitamin D combination therapy modulates inflammatory response after traumatic brain injury. - PubMed - NCBI
1,25(OH)2D3 downregulates the Toll-like receptor 4-mediated inflammatory pathway and ameliorates liver injury in diabetic rats. - PubMed - NCBI
[Effect of 1,25-(OH)2D3 on expression of HMGB1 and TLR4 in the lungs of asthmatic mice]. - PubMed - NCBI
1,25(OH)2D3-mediated amelioration of aortic injury in streptozotocin-induced diabetic rats. - PubMed - NCBI
25-Hydroxyvitamin D3 attenuates experimental periodontitis through downregulation of TLR4 and JAK1/STAT3 signaling in diabetic mice. - PubMed - NCBI
Vitamin D3 ameliorates herpes simplex virus-induced Behçet's disease-like inflammation in a mouse model through down-regulation of Toll-like recept... - PubMed - NCBI
Influence of 1,25-dihydroxy vitamin D3 on TLR4-induced activation of antigen presenting cells is dependent on the order of receptor engagement. - PubMed - NCBI
http://www.ncbi.nlm.nih.gov/pubmed/20214986
http://www.ncbi.nlm.nih.gov/pubmed/16367934
Human studies:
http://www.ncbi.nlm.nih.gov/pubmed/26770399
http://www.ncbi.nlm.nih.gov/pubmed/24373795
http://www.ncbi.nlm.nih.gov/pubmed/16402404
Finally, even high doses vitamin D3 used in some of these studies did not cause hypercalcemia, so the most feared side effect of vitamin D is apparently not that common.
"...Consistent with these findings, our results showed that high-dose 1,25(OH)2D3 administration could significantly protect against liver inflammation and fibrosis in diabetic rats. However, some larger, randomized, placebo-controlled trials are required to detect the effects of vitamin D supplementation for the treatment of NAFLD and to determine the optimal levels of vitamin D. Furthermore, we found that the expression of TLR4, NF-κB, and TNF-α was downregulated by 1,25(OH)2D3 in a dose-dependent manner. We also observed differences in CD68 staining among groups, indicating changes in Kupffer cell/macrophage numbers. Many of the changes observed in the liver were secondary to the changes in Kupffer cell numbers, and these alterations may mediate the anti-inflammatory effects of high-dose 1,25(OH)2D3 in the liver of diabetic rats. Because high-dose 1,25(OH)2D3 may lead to problems such as hypercalcemia, we also tested serum calcium and phosphate levels. Our results showed that the levels of serum calcium and phosphate in rats treated with 1,25(OH)2D3 were not significantly different compared with those in normal rats."
Animal studies:
Vitamin D [1,25(OH)2D3] Differentially Regulates Human Innate Cytokine Responses to Bacterial versus Viral Pattern Recognition Receptor Stimuli. - PubMed - NCBI
Vitamin D inhibits lipopolysaccharide-induced inflammatory response potentially through the Toll-like receptor 4 signalling pathway in the intestin... - PubMed - NCBI
Progesterone and vitamin D combination therapy modulates inflammatory response after traumatic brain injury. - PubMed - NCBI
1,25(OH)2D3 downregulates the Toll-like receptor 4-mediated inflammatory pathway and ameliorates liver injury in diabetic rats. - PubMed - NCBI
[Effect of 1,25-(OH)2D3 on expression of HMGB1 and TLR4 in the lungs of asthmatic mice]. - PubMed - NCBI
1,25(OH)2D3-mediated amelioration of aortic injury in streptozotocin-induced diabetic rats. - PubMed - NCBI
25-Hydroxyvitamin D3 attenuates experimental periodontitis through downregulation of TLR4 and JAK1/STAT3 signaling in diabetic mice. - PubMed - NCBI
Vitamin D3 ameliorates herpes simplex virus-induced Behçet's disease-like inflammation in a mouse model through down-regulation of Toll-like recept... - PubMed - NCBI
Influence of 1,25-dihydroxy vitamin D3 on TLR4-induced activation of antigen presenting cells is dependent on the order of receptor engagement. - PubMed - NCBI
http://www.ncbi.nlm.nih.gov/pubmed/20214986
http://www.ncbi.nlm.nih.gov/pubmed/16367934
Human studies:
http://www.ncbi.nlm.nih.gov/pubmed/26770399
http://www.ncbi.nlm.nih.gov/pubmed/24373795
http://www.ncbi.nlm.nih.gov/pubmed/16402404