Hyperlipidemias: Akizawa T

Kuroki A, Akizawa T. · Department of Nephrology, Showa University, School of Medicine. · Nippon Rinsho. · Pubmed #18788403 No free full text.

Abstract: Intraglomerular hypertension, and glomerular hypertrophy, leading to glomerular scarring are suggested to have an effect on the progression in chronic kidney disease, unrelated to the initial cause of kidney injury. Tubulointerstitial disease is another factor, which may affect the prognosis. Strategies to prevent or minimize the progression of kidney disease consist of treating these disease-worsening mechanisms, including smoking cessation, treatment of hyperlipidemia, sodium and protein restriction, antihypertensive therapy, inhibition of renin-angiotensin-aldosterone system, and treatment of anemia. Studies in experimental animals and humans suggest that these therapies are effective to prevent the progression in chronic kidney disease and there are some evidences that these therapies have benefits in the patients with chronic kidney disease.

Ichikawa H, Takahashi N, Mukai M, Akizawa T, Kawamura M. · Department of Neurology, Showa University School of Medicine, Tokyo, Japan. · J Stroke Cerebrovasc Dis. · Pubmed #18984434 No free full text.

Abstract: BACKGROUND: We encountered asymptomatic large T2 high-signal pontine lesion (PL) with peachlike configurations on magnetic resonance imaging. The objective of this study was to determine the pathogenic factors for such PLs and to differentiate PL from ischemic rarefaction. METHODS: We compared the clinical backgrounds of 37 patients with PL and 100 patients without PL, including conventional atherosclerotic risk factors, chronic kidney disease (CKD) defined as an estimated glomerular filtration rate less than 60 mL/min/1.73 m(3), and the degree of supratentorial deep white matter hyperintensities (DWMH). The chronologic alternations in PL were also reviewed. RESULTS: Patients with PL had a much higher incidence of diabetes mellitus (DM) and CKD as compared with patients without PL: 54% versus 15% for DM (P < .001) and 57% versus 29% for CKD (P < .05). PL did not necessarily accompany DWMH and its degree did not correlate with PL. Further analyses showed that patients with PL without DWMH had a much higher incidence of DM and CKD as compared with patients with DWMH without PL: 85% versus 6% for DM (P < .0001) and 85% versus 50% for CKD (P < .05). Chronologically, PLs expanded, shrunk, or fluctuated in size in 5 patients with DM and CKD. CONCLUSIONS: We demonstrated that DM and CKD are important for PL and that the backgrounds of PL were inconsistent with DWMH. These results and the chronologic alternations in PL suggested that metabolic factors other than ischemic rarefaction played important roles in the development of PL.

Liang XM, Otani H, Zhou Q, Tone Y, Fujii R, Mune M, Yukawa S, Akizawa T. · Department of Nephrology, Qilu Hospital of Shandong University, Shandong Province, China. · Nephrol Dial Transplant. · Pubmed #17550926 links to  free full text

Abstract: BACKGROUND: Independent of their lipid-lowering effects, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have renal protective effects on various models of progressive renal diseases, therefore, additional therapeutic advantages have been considered. In the present study, using spontaneously hypercholesterolaemic Imai rats, we examined the protective effects of pitavastatin on renal injuries and the oxidative modification of the low-density lipoprotein (LDL) and high-density lipoprotein (HDL), since oxidized lipoproteins are speculated to be involved in the mechanism of this rat strain's renal injuries. METHODS: Male Imai rats were treated with pitavastatin (n = 11) at a dose of 100 mg/kg diet or received no specific therapy as controls (n = 11) from 10 to 22 weeks of age. Body weight, urinary protein excretion and serum constituents were evaluated every 4 weeks. At the end of the study, the effects of pitavastatin on the susceptibility of serum LDL and HDL to oxidation, and renal histology were examined. RESULTS: Pitavastatin treatment did not affect hyperlipidaemia, but significantly reduced proteinuria and preserved creatinine clearance deterioration. At the end of the study, lag times for LDL and HDL oxidation were prolonged by the treatment of pitavastatin to 126 and 153%, respectively, compared with the controlled group. The glomerulosclerosis index (SI) for untreated controlled rats was significantly higher than that for the pitavastatin-treated group. An immunohistochemistry study showed significantly lower numbers of ED-1 positive macrophages in the glomeruli and interstitium in pitavastatin-treated rats compared with those controlled. CONCLUSION: Pitavastatin treatment prevented renal injuries in Imai rats independent of lipid-lowering effects. Prevention of oxidative modification of LDL and HDL may play an important role on the beneficial effects of pitavastatin treatment.

Liang XM, Otani H, Zhou Q, Tone Y, Fujii R, Mune M, Yukawa S, Akizawa T. · Department of Nephrology, Qilu Hospital of Shandong University, Jinan, China. · Nephron Exp Nephrol. · Pubmed #17347583 No free full text.

Abstract: BACKGROUND/AIM: Dietary protein restriction is known to be beneficial in the preservation of the renal function in patients with chronic renal failure. Recently, the effect of varying quantity and quality of dietary protein intakes was also studied. This study investigates the effects of different dietary animal proteins on renal function in spontaneously hypercholesterolemic Imai rats that exhibit renal lesions similar to human focal and segmental glomerulosclerosis. The sources of proteins were from casein, pork, and fish. Primary concern was the effect of fish meat protein, because the effects of fish oil are well reported. To examine whether remnants of fish oil affect the experimental results, semi-defatted fish meat and fully defatted fish meat were prepared for these experiments. METHODS: Forty-two Imai rats were placed on diets containing casein, defatted pork meat, semi-defatted fish meat, or defatted fish meat as a protein sources from 10 to 22 weeks of age. Twenty-four hour urine collections were obtained along with measurements of systolic blood pressure and drawing blood from the tail artery every 4 weeks. Finally, the kidneys were removed and prepared for histological study. RESULTS: The semi-defatted fish meat diet retarded the rise of plasma cholesterol, virtually completely prevented the development of hypertriglyceridemia, and slowed the progression of proteinuria, renal function failure, and glomerular injury as compared with the control casein diet. However, the fully defatted fish meat diet led to renal failure at the same rate as the casein diet. The defatted pork diet group exhibited a higher creatinine clearance at the end of the experiments as compared with the casein and the fully defatted fish meat diet groups. CONCLUSIONS: These data suggest that an important determinant of the protective effects of the semi-defatted fish meat diet was related to the prevention of hypercholesterolemia and hypertriglyceridemia by the remaining fish oil. Fish meat protein itself did not indicate superior beneficial effects in the regression of the renal function in Imai rats as compared with casein protein, and defatted pork showed better results than casein and fully defatted fish meat.