Genetic background, recent advances in molecular biology, and development of novel therapy in Alport syndrome

Alport syndrome (AS) is a progressive inherited kidney disease characterized by hearing loss and ocular abnormalities.There are three forms of AS depending on inheritance mode: X-linked Alport syndrome (XLAS), autosomal recessive AS (ARAS), and autosomal dominant AS (ADAS). XLAS is caused by pathogenic variants in COL4A5, which encodes type IV collagen α5 chain, while ADAS and ARAS are caused by variants in COL4A3 or COL4A4, which encode type IV collagen α3 or α4 chain, respectively. In male XLAS or ARAS cases, end-stage kidney disease (ESKD) develops around a median age of 20 to 30 years old, while female XLAS or ADAS cases develop ESKD around a median age of 60 to 70 years old. The diagnosis of AS is dependent on either genetic or pathological findings. However, determining the pathogenicity of the variants detected by gene tests can be difficult. Recently, we applied the following molecular investigation tools to determine pathogenicity: 1) in silico and in vitro trimer formation assay of α345 chains to assess triple helix formation ability, 2) kidney organoids constructed from patients’ induced pluripotent stem cells to identify α5 chain expression on the glomerular basement membrane, and 3) in vitro splicing assay to detect aberrant splicing to determine the pathogenicity of variants. In this review article, we discuss the genetic background and novel assays for determining the pathogenicity of variants. We also discuss the current treatment approaches and introduce exon skipping therapy as one potential treatment option.

Genetic background, recent advances in molecular biology, and development of novel therapy in Alport syndrome

Alport syndrome (AS) is a progressive inherited kidney disease characterized by hearing loss and ocular abnormalities.There are three forms of AS depending on inheritance mode: X-linked Alport syndrome (XLAS), autosomal recessive AS (ARAS), and autosomal dominant AS (ADAS). XLAS is caused by pathogenic variants in COL4A5, which encodes type IV collagen α5 chain, while ADAS and ARAS are caused by variants in COL4A3 or COL4A4, which encode type IV collagen α3 or α4 chain, respectively. In male XLAS or ARAS cases, end-stage kidney disease (ESKD) develops around a median age of 20 to 30 years old, while female XLAS or ADAS cases develop ESKD around a median age of 60 to 70 years old. The diagnosis of AS is dependent on either genetic or pathological findings. However, determining the pathogenicity of the variants detected by gene tests can be difficult. Recently, we applied the following molecular investigation tools to determine pathogenicity: 1) in silico and in vitro trimer formation assay of α345 chains to assess triple helix formation ability, 2) kidney organoids constructed from patients’ induced pluripotent stem cells to identify α5 chain expression on the glomerular basement membrane, and 3) in vitro splicing assay to detect aberrant splicing to determine the pathogenicity of variants. In this review article, we discuss the genetic background and novel assays for determining the pathogenicity of variants. We also discuss the current treatment approaches and introduce exon skipping therapy as one potential treatment option.

Molecular Mechanisms of Inhibiting the Muscle Atrophy by Electroacupuncture / 日本温泉気候物理医学会雑誌

 Electroacupuncture (EA) is an acupuncture technique that is stimulated by acupuncture needles with low-frequency microcurrent. The aim of this study is to elucidate the effect of EA and it's molecular mechanism on muscle atrophy by using an animal model: hindlimb-suspended (HS) mice in the disuse muscle atrophy model. To compare the effects of EA in HS mice and HS mice treated with EA (EA/HS), soleus muscle mass and soleus myofiber diameter were measured. We then used real-time quantitative RT-PCR to analyze the expression of myostatin and ubiquitin ligase genes in atrophic muscles of HS mice and in muscles of EA/HS mice. We found that EA/HS mice maintained a soleus muscle mass that was not significantly different from that of wild mice (WT), whereas HS mice had significantly reduced muscle mass. Also, the diameters of myofibers in EA/HS mice, which were not significantly different from wild values, were significantly larger than those in HS mice. Repeated EA treatment suppressed gene expression of myostatin and ubiquitin ligase genes in skeletal muscle of EA/HS mice but induced expression of these genes in HS mice. These findings suggest the molecular mechanism by EA: suppression of myostatin and ubiquitin ligase gene may be a key reaction of inhibiting the disuse muscle atrophy.

Molecular Mechanisms of Inhibiting the Muscle Atrophy by Electroacupuncture / 日本温泉気候物理医学会雑誌

 Electroacupuncture (EA) is an acupuncture technique that is stimulated by acupuncture needles with low-frequency microcurrent. The aim of this study is to elucidate the effect of EA and it's molecular mechanism on muscle atrophy by using an animal model: hindlimb-suspended (HS) mice in the disuse muscle atrophy model. To compare the effects of EA in HS mice and HS mice treated with EA (EA/HS), soleus muscle mass and soleus myofiber diameter were measured. We then used real-time quantitative RT-PCR to analyze the expression of myostatin and ubiquitin ligase genes in atrophic muscles of HS mice and in muscles of EA/HS mice. We found that EA/HS mice maintained a soleus muscle mass that was not significantly different from that of wild mice (WT), whereas HS mice had significantly reduced muscle mass. Also, the diameters of myofibers in EA/HS mice, which were not significantly different from wild values, were significantly larger than those in HS mice. Repeated EA treatment suppressed gene expression of myostatin and ubiquitin ligase genes in skeletal muscle of EA/HS mice but induced expression of these genes in HS mice. These findings suggest the molecular mechanism by EA: suppression of myostatin and ubiquitin ligase gene may be a key reaction of inhibiting the disuse muscle atrophy.

Electroacupuncture accelerates recovery of muscle atrophy induced by hindlimb suspension in mouse skeletal muscle / 全日本鍼灸学会雑誌

[Objective]The influence of electroacupuncture (EA) stimulation on physical inactivity is not clear. This study aimed to investigate the effects of EA on the recovery of mouse soleus muscle atrophy induced by hindlimb suspension (HS).<BR>[Methods]We used 8-week-old male ICR mice (n = 20). The mice were divided into 4 groups:the No treatment group (NT, n = 5), HS group (HS, n = 5), Control group (CT, n = 5), and Reloading-with-EA-stimulation group (EA, n = 5). HS mice were suspended for up to 14 days. CT and EA mice were reloaded for an additional 14 days after the HS for 14 days. The HS method used a modified version of an apparatus used in a previous study. EA mice received EA every other day immediately after reloading and were stimulated in the triceps surae muscle at 10 Hz for 30 min with a stainless steel needle. The weight, muscle fiber area size and number of macrophages in the soleus muscle were analyzed.<BR>[Results]The number of skeletal muscle macrophages was increased significantly in EA mice compared with that in CT mice (P < 0.01). The soleus muscle weight and muscle fiber cross-sectional area were decreased in HS mice compared with NT mice (P < 0.01). However, the muscle weight of EA and CT mice increased significantly compared with that of HS mice (P < 0.01). In addition, the muscle weight of EA mice was significantly higher than that of CT mice (P < 0.01), without a significant difference in muscle fiber cross-sectional area between CT and EA mice. <BR>[Conclusion]These results indicate that EA was effective in facilitating the recovery of skeletal muscle atrophy in mice. In addition, resolution of the skeletal muscle atrophy suggested the satellite cell activation by macrophages, because macrophages invaded the skeletal muscle after EA stimulation.

Acupuncture Medicine in the Century of Genome Medicine: Evidence from Genome Science / 全日本鍼灸学会雑誌

Genome Medicine and Acupuncture Medicine have a common attempt to explain them with one keyword, that is, DNA and Qi. I was taught at Meiji University of Oriental Medicine that Oriental Medicine had the advantage of personalized treatment along with the individual's physical conditions while Western Medicine provides standardized treatment. In addition, treating Mibyou (potential disease) was considered. However, this priority is not unique to Oriental Medicine because Genome Medicine aims at personalized medicine or preventive medicine.<br>In this paper, I introduce: 1) research trends towards personalized medicine, 2) reconstitution of genomic information and its clinical application, 3) the significance of acupuncture research from a genomic point of view and its achievements (Takaoka et al.: Articles in Press, Physiol Genomics, March 6, 2007). This Special Lecture was updated with additional data and findings from Physiological Genomics.<br><br>“The most proper way to unify all disciplines is to study and unite them by yourself.” (“Challenges to Science” (in Japanese) by Professor Hitoshi Takeuchi and Professor Takeshi Umehara)