Human COQ4 deficiency: delineating the clinical, metabolic and neuroimaging phenotypes.

BACKGROUND: Human coenzyme Q4 (COQ4) is essential for coenzyme Q10 (CoQ10) biosynthesis. Pathogenic variants in COQ4 cause childhood-onset neurodegeneration. We aimed to delineate the clinical spectrum and the cellular consequences of COQ4 deficiency. METHODS: Clinical course and neuroradiological findings in a large cohort of paediatric patients with COQ4 deficiency were analysed. Functional studies in patient-derived cell lines were performed. RESULTS: We characterised 44 individuals from 36 families with COQ4 deficiency (16 newly described). A total of 23 different variants were identified, including four novel variants in COQ4. Correlation analyses of clinical and neuroimaging findings revealed three disease patterns: type 1: early-onset phenotype with neonatal brain anomalies and epileptic encephalopathy; type 2: intermediate phenotype with distinct stroke-like lesions; and type 3: moderate phenotype with non-specific brain pathology and a stable disease course. The functional relevance of COQ4 variants was supported by in vitro studies using patient-derived fibroblast lines. Experiments revealed significantly decreased COQ4 protein levels, reduced levels of cellular CoQ10 and elevated levels of the metabolic intermediate 6-demethoxyubiquinone. CONCLUSION: Our study describes the heterogeneous clinical presentation of COQ4 deficiency and identifies phenotypic subtypes. Cell-based studies support the pathogenic characteristics of COQ4 variants. Due to the insufficient clinical response to oral CoQ10 supplementation, alternative treatment strategies are warranted.

An Updated Review of Various Medicinal Applications of p-Co umaric Acid: From Antioxidative and Anti-Inflammatory Properties to Effects on Cell Cycle and Proliferation.

P-Coumaric acid (p-CA) is a hydroxycinnamic acid, an organic compound that is a hydroxyl derivative of cinnamic acid. P-CA is the most abundant isomer in nature and can be found in a wide variety of edible plants such as fungi, peanuts, navy beans, tomatoes, carrots, basil, and garlic. Recently, the therapeutic properties of p-CA have received a great deal of attention from scientific society. Here, we described the medicinal effects of p-CA on various pathological conditions. This review was performed via evaluating PubMed reported studies from January 2010 to January 2020. Also, reference lists were checked to find additional studies. All intermediation or complementarity of animal models, case-control and cohort studies, in vitro studies, and controlled trials (CTs) on p-CA were acceptable. However plant extract studies without indication of main active substances were excluded due to the considerable diversities and heterogeneities. According to recent evidence regarding the beneficial effects of p-CA, numerous diseases such as nephropathies, cardiovascular diseases, neuroinflammatory diseases, liver diseases, cancers, and some metabolic disorders could potentially be controlled by this natural herb. Interestingly, autophagy is a novel molecular mechanism involved in the crosstalk between classic effects of p-CA and introduces alternative therapeutic pathways for this compound. Much work remains in clarifying the main therapeutic properties among the various p-CA effects; these will be the subject of forthcoming work, resulting in presenting further mechanism of action.