The phenylalanine–tyrosine–dopa–dopamine pathway provides dopamine to the brain. In this process, tyrosine hydroxylase (TH) is the rate-limiting enzyme that hydroxylates tyrosine and generates levodopa (l-dopa) with tetrahydrobiopterin (BH4) as a coenzyme. Here, we show that oral berberine (BBR) might supply H• through dihydroberberine (reduced BBR produced by bacterial nitroreductase) and promote the production of BH4 from dihydrobiopterin; the increased BH4 enhances TH activity, which accelerates the production of l-dopa by the gut bacteria. Oral BBR acts in a way similar to vitamins. The l-dopa produced by the intestinal bacteria enters the brain through the circulation and is transformed to dopamine. To verify the gut–brain dialog activated by BBR’s effect, Enterococcus faecalis or Enterococcus faecium was transplanted into Parkinson’s disease (PD) mice. The bacteria significantly increased brain dopamine and ameliorated PD manifestation in mice; additionally, combination of BBR with bacteria showed better therapeutic effect than that with bacteria alone. Moreover, 2,4,6-trimethyl-pyranylium tetrafluoroborate (TMP-TFB)-derivatized matrix-assisted laser desorption mass spectrometry (MALDI-MS) imaging of dopamine identified elevated striatal dopamine levels in mouse brains with oral Enterococcus, and BBR strengthened the imaging intensity of brain dopamine. These results demonstrated that BBR was an agonist of TH in Enterococcus and could lead to the production of l-dopa in the gut. Furthermore, a study of 28 patients with hyperlipidemia confirmed that oral BBR increased blood/fecal l-dopa by the intestinal bacteria. Hence, BBR might improve the brain function by upregulating the biosynthesis of l-dopa in the gut microbiota through a vitamin-like effect.

Dominant inheritance of osteogenesis imperfecta (OI) is caused by mutations in COL1A1 or COL1A2, the genes that encode type I collagen, and CRTAP, LEPRE1, PPIB, FKBP10, SERPINH1, and SP7 mutations were recently detected in a minority of patients with autosomal recessive OI. However, these findings have been mostly restricted to Western populations. The proportion of mutations and the correlations between genotype and phenotype in Chinese patients with OI are completely unknown. In this study, mutation analyses were performed for COL1A1, COL1A2, CRTAP, and LEPRE1 in a cohort of 58 unrelated Chinese patients with OI; the relationship between collagen type I mutations and clinical features was examined. A total of 56 heterozygous mutations were identified in COL1A1 and COL1A2, including 43 mutations in COL1A1 and 13 mutations in COL1A2. Among the 56 causative COL1A1 and COL1A2 mutations, 24 novel mutations were found, and 25 (44.6%) resulted in the substitution of a glycine within the Gly-X-Y triplet domain of the triple helix. Compared with COL1A1 haploinsufficiency (n = 23), patients with mutations affecting glycine residues had a severe skeletal phenotype. In patients 18 years of age or older, on average patients with COL1A1 haploinsufficiency were taller and had higher femoral neck bone mineral density than with patients with helical mutations. Interestingly, we found two novel compound heterozygous mutations in the LEPRE1 gene in two unrelated families with autosomal recessive OI. Although the genotype-phenotype correlation is still unclear, our findings are useful to understand the genetic basis of Chinese patients with OI.

Patients with AF have abnormal electrophysiologic substrate in sinus rhythm characterized by lower mean bipolar voltage, more prevalent complex electrograms, and longer LA activation time. This substrate progresses parallel to progression of AF type.