Toxic Effects of Indoxyl Sulfate on Osteoclastogenesis and Osteoblastogenesis.

Uremic toxins, such as indoxyl sulfate (IS) and kynurenine, accumulate in the blood in the event of kidney failure and contribute to further bone damage. To maintain the homeostasis of the skeletal system, bone remodeling is a persistent process of bone formation and bone resorption that depends on a dynamic balance of osteoblasts and osteoclasts. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates the toxic effects of uremic toxins. IS is an endogenous AhR ligand and is metabolized from tryptophan. In osteoclastogenesis, IS affects the expression of the osteoclast precursor nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) through AhR signaling. It is possible to increase osteoclast differentiation with short-term and low-dose IS exposure and to decrease differentiation with long-term and/or high-dose IS exposure. Coincidentally, during osteoblastogenesis, through the AhR signaling pathway, IS inhibits the phosphorylation of ERK, and p38 reduces the expression of the transcription factor 2 (Runx2), disturbing osteoblastogenesis. The AhR antagonist resveratrol has a protective effect on the IS/AhR pathway. Therefore, it is necessary to understand the multifaceted role of AhR in CKD, as knowledge of these transcription signals could provide a safe and effective method to prevent and treat CKD mineral bone disease.

Qi deficiency is associated with depression in chronic hemodialysis patients.

OBJECTIVE: Depression is a common bio-psycho-social problem in hemodialysis (HD) patients. Traditional Chinese medicine has been used for symptom management in patients with depression. Identification of the specific constitution in traditional Chinese medicine is critical for personalized care. However, the association between depression and specific constitution in HD patients is unknown. METHODS: We conducted a cross-sectional study in all chronic HD patients (HD for more than 3 months) at China Medical University Hospital in Taiwan. The depression symptom severity was determined using the Beck Depression Inventory II (BDI-II). Clinical patterns in Chinese medicine were determined using the Constitution in Chinese Medicine Questionnaire. The association between constitution and depression was analyzed using logistic regression. RESULTS: We recruited 467 chronic hemodialysis patients, including 219 females and 248 males, with a mean age of 63±12years. The mean duration of HD was 5.8 years. The mean score for the BDI-II was 11 (interquartile range 8-14). The major constitution was Yang-deficiency (43.7%) among these chronic HD patients. Qi-deficiency was correlated with a duration of HD of more than 5.8 years (p=0.04). Qi-deficiency [odds ratio (OR): 4.05, 95% confidence interval (CI): 1.69-9.72, p<0.01] was also associated with depression in logistic regression with adjustments for confounders, including calcium, phosphorus and hemoglobin levels. CONCLUSION: Qi-deficiency constitution in Chinese medicine is associated with depression in chronic HD patients. Further studies are needed to determine whether treating Qi-deficiency integrating Chinese medicine treatment can improve patients' depression symptoms.

Patient education: an efficient adjuvant therapy for hyperphosphatemia in hemodialysis patients.

BACKGROUND: Hemodialysis and phosphate (P) binder therapy are the major methods to reduce the phosphate level in dialysis patients. However, dietary P restriction is necessary for adequate control. The successful dietary control is based on patient compliance. Patient education is the best method to assure the knowledge and drive of dietary control, which are the key features for patient compliance. The aim of the study is to investigate quantitatively the effect of patient education on serum P levels in hyperphosphatemic hemodialysis patients. METHODS: We conducted a prospective self-control study. Fifty hemodialysis patients with a pre-dialysis serum P level greater than 6.0 mg/dL were studied. Intensified patient education was given. Serum P, calcium (Ca), and intact parathyroid hormone (iPTH) were evaluated before and one month after patient education. RESULTS: Thirty-six (72%) patients had improved pre-dialysis P level (pre-education: 7.50 +/- 1.33; post-education: 5.85 +/- 1.20 mg/dL, p < 0.001) and Ca x P product (pre-education: 68.17 +/- 12.70; post-education: 54.70 +/- 11.87 mg(2)/dL(2), p < 0.001). The effect lasted for at least three months. There is no significant change on calcium levels. The only predictor of a successful patient education is the iPTH level (improved: 348.8 +/- 277.6; non-improved: 668.0 +/- 674.1 ng/mL, p = 0.021). CONCLUSIONS: Patient education could be helpful and efficient in hyperphosphatemic control in dialysis patients. The patient education should be given before the serum iPTH level getting high.