Search

Recognition of early stage of diabetic kidney disease, under common practice using biomarkers, namely microalbuminuria, serum creatinine level above 1 mg/dL and accepted definition of diabetic kidney disease associated with creatinine clearance value below 60 mL/min/1.73 m2, is unlikely. This would lead to delay treatment associated with therapeutic resistance to vasodilator due to a defective vascular homoeostasis. Other alternative biomarkers related to the state of microalbuminuria is not sensitive to screen for early diabetic kidney disease (stages I, II). In this regard, a better diagnostic markers to serve for this purpose are creatinine clearance, fractional excretion of magnesium (FE Mg), cystatin C. Recently, renal microvascular disease and renal ischemia have been demonstrated to correlate indirectly with the development of diabetic kidney disease and its function. Among these are angiogenic and anti-angiogenic factors, namely VEGF, VEGF receptors, angiopoietins and endostatin. With respect to therapeutic prevention, implementation of treatment at early stage of diabetic and nondiabetic kidney disease is able to restore renal perfusion and function.

Under common practice, treatment of diabetic nephropathy (DN) is usually initiated at late stage of CKD due to the insensitiveness of the available diagnostic markers. Such treatment fails to restore renal perfusion and function. This is due to the defective mechanism of vascular homeostasis and impaired nitric oxide production observed in late stage of DN. In contrast, the mechanism of vascular repair is adequately functional in early stage of DN (normoalbuminuria). In this study, we treated 50 normoalbuminuric diabetic patients with multidrug vasodilators, namely ACE inhibitor, angiotensin receptor blocker, ± calcium channel blocker in conjunction with correction of metabolic disorders for 24-36 months. Following the treatment, increment in peritubular capillary flow in response to vasodilators was observed, and thus supports the adequate role of vascular repair. In addition, increase in renal function documented in this study also implies that an effective preventive strategy to minimize end-stage renal disease can be accomplished in normoalbuminuric DN.

Background: Renal microvascular disease and reduction in peritubular capillary flow are generally observed in type 2 diabetic nephropathy (DN). Earlier therapeutic strategy with vasodilators has improved renal function in normo-albuminuric type 2 DN. Objective: Study the mechanism of vascular homeostasis in twenty patients associated with normo-albuminuric type 2 DN. Results: Angiogenic factors were observed in normo-albuminuric type 2 DN, where vascular endothelial growth factor (VEGF), was 420 + 341 vs. 428+291 pg/mL (normal), and vascular endothelial growth factor - receptor 1 (VEGF-R1) was 60+12 vs. 49+5 ng/mL (normal), which were not significantly different from the controls. Anti-angiogenic factors were observed in normo-albuminuric type 2 DN, where angiopoietin-2, was 2309+1125 vs. 1671+835 pg/mL (normal), and vascular endothelial growth factor - receptor 2 (VEGF-R2) was 5715+1400 vs.6126 + 1060 ng/mL (normal), which were not significantly different from the controls. Conclusion: The mechanism of vascular homeostasis was adequately functional in normo-albuminuric type 2 DN. This mechanism may explain the positive response to vasodilators and improved renal function in early stage of type 2 DN following the vasodilator treatment. Keywords: Enhanced renal perfusion, normo-albuminuric type 2 diabetic nephropathy, vascular homeostasis, restoring renal function

Background: Treatment with vasodilators can improve renal function in early stage of chronic kidney disease (CKD) patients. Objective: Study the mechanism of vascular repair in 20 CKD patients associated with actual creatinine clearance greater than 60 mL/min/1.73m2 (mean 84+24 mL/min/1.73m2) who had been under treatment with vasodilators. Results: Initial study on angiogenic factors revealed a low value of VEGF, no significant change in VEGF-R1, whereas antiangiogenic factors showed elevated angiopoietin-2 and no significant change in VEGF-R2. Initial actual creatinine clearance was significantly depleted and fractional excretion of magnesium (FE Mg) was elevated significantly. Follow-up study showed improved VEGF and a significant decline in angiopoietin-2. Such improved vascular repair coincided with enhanced creatinine clearance. Conclusion: Improved renal function can be achieved by vasodilators under environment favourable for adequate vascular repair.

A continuous increase in number of CKD patients entering ESRD is a growing public health threat, which reflects the present therapeutic failure usually initiating at the late stage of CKD.To study the mechanism of vascular repair in CKD patients associated with mildly impaired renal function, which included angiogenic factors such as VEFG, angiopoietin-1, and flt-1 (VEGFR1); and antiangiogenic factors such as angiopoietin-2 and KDR (VEGFR2).A mild defect in angiogenic factor-namely, angiopoietin-1-was observed, whereas VEGF and flt-1 (VEGFR1) were within normal limit. Also, antiangiogenic factor-namely, angiopoietin-2-was mildly elevated, whereas KDR (VEGFR2) remained within normal limit.The mechanism of vascular repair appears to be adequately functional in the early stage of CKD. Therapeutic intervention at this stage can improve renal perfusion and restore renal function as indicated in normoalbuminuric, type 2 diabetic nephropathy. The authors encourage changing the conceptual view of treatment under common treatment at late stage of CKD to treatment at early stage of CKD under an environment favorable for renal regeneration.

Type 2 diabetic nephropathy is a primary cause of ESRD worldwide. Therapeutic strategy in patients with microalbuminuric or macroalbuminuric type 2 diabetic nephropathy usually fails to restore renal function but merely slows the renal disease progression. In contrast, a recent study implies that the restoration of renal function as well as renal perfusion can be accomplished in early stage of type 2 diabetic nephropathy (normoalbuminuria) by correcting the hemodynamic maladjustment in renal microcirculation with vasodilators. Therefore, we intend to study the mechanism of vascular homeostasis to explain why treatment in the late stage of diabetic nephropathy during microalbuminuria or macroalbuminuria fails to enhance renal perfusion or restore renal function. The results indicate that such therapeutic failure in late-stage type 2 diabetic nephropathy likely relates to multiple defects in vascular repair, namely deficiencies in angiogenic factors such as endothelial progenitor cell, angiopoietin-1, flt-1 receptor, as well as elevated levels of antiangiogenic factors such as angiopoietin-2 and KDR.

Renal microvascular disease and tubulointerstitial fibrosis are usually demonstrated in aging in humans and animals. It has recently been proposed that renal microvascular disease is the crucial determinant of tubulointerstitial disease or fibrosis. Enhanced circulating endothelial cell loss is a biomarker that reflects glomerular endothelial injury or renal microvascular disease, and fractional excretion of magnesium (FE Mg) is a sensitive biomarker that reflects an early stage of tubulointerstitial fibrosis. In aging in humans, both of these biomarkers are abnormally elevated. In addition, a glomerular endothelial dysfunction determined by altered hemodynamics associated with peritubular capillary flow reduction is substantiated. A correction of such hemodynamic alteration with vasodilators can effectively improve renal perfusion and restore renal function. Thus, anti-aging therapy can reverse the renal microvascular disease and dysfunction associated with the aging process.

Therapeutic failure in preventing renal disease progression in type 2 diabetic nephropathy (DN) is due to a failure in the early detection of DN by microalbuminuria and the inappropriate correction of renal hemodynamic maladjustment secondary to glomerular endothelial dysfunction.Thirty patients associated with normoalbuminuric type 2 DN were subject to the following studies: tubular function by means of fractional excretion of magnesium (FE Mg), vascular function by means of determining the circulating endothelial cell, VEGF, VEGF/TGF B ratio, and intrarenal hemodynamic studies.FE Mg, circulating endothelial cells, and TGF B were abnormally elevated, and VEGF/TGF B ratio was decreased in these normoalbuminuric patients. The intrarenal hemodynamic study revealed a hemodynamic maladjustment characterized by a preferential constriction at the efferent arteriole and a reduction in peritubular capillary flow. Following treatment with vasodilators, a decrease in efferent arteriolar resistance and increase in peritubular capillary flow as well as glomerular clearance were observed.FE Mg appears to be a more sensitive marker than microalbuminuria for the early detection of DN. Increased endothelial cell injury is reflected by enhanced circulating endothelial cell loss in conjunction with the increased TGF B and the decreased ratio between VEGF and TGF B. This is further supported by the dysfunctioning glomerular endothelium, which is characterized by hemodynamic maladjustment and a reduction in the peritubular capillary flow. A correction of such hemodynamic maladjustment by multidrug vasodilators effectively improves renal perfusion and restores renal function in type 2 DN.

Early stage of vascular disease and diabetic kidney disease (DKD stages 1 and 2) has been under-recognized, under common practice worldwide. The lack of sensitive diagnostic marker leads to late diagnosis and a progression of underlying vascular disease associated with chronic renal ischemia, which eventually intensifies the magnitude of DKD damage. Treatment at this late stage fails to correct the renal ischemia, or restore renal function, due to the altered vascular homeostasis associated with an impaired nitric oxide production. In contrast to the above information, early recognition of vascular disease and DKD with sensitive diagnostic markers would be able to implement an effective prevention of progression of vascular disease and DKD. Treatment at early stage under environment favorable for adequate vascular homeostasis is able to correct the renal ischemia and improve the renal function.

Idiopathic nephrotic syndrome (NS) associated with focal segmental glomerulosclerosis (FSGS) and severe renal function impairment is usually refractory to the conventional treatment and progresses to end-stage renal disease. Herein, we reported 10 patients with NS-FSGS who had initially had CCr 34 +/- 12 mL/min/1.73 m2 (normal 120 mL/min/1.73 m2), FE Mg 7.8 +/- 2.6% (normal 2.2%), 24-h urinary protein 3.1 g (normal200 mg) and been followed up for over 10 years. The initial intrarenal hemodynamic study revealed a marked elevation of efferent arteriolar resistance (RE 17289 +/- 8636 dyne x s x cm(-5); normal 3000 dyne x s x cm(-5)), intraglomerular hypertension (PG 57 +/- 1 mm Hg; normal 52 mm Hg), hyperfiltration (FF 0.24; normal 0.2), marked reductions in GFR 35 +/- 17 mL/min/1.73 m2, renal plasma flow (RPF 159 +/- 61 mL/min/1.73 m2; normal 600 mL/min/1.73 m2) and peritubular capillary flow (PTCF 123 +/- 57 mL/min/1.73 m2; normal 480 mL/min/1.73 m2). Such a hemodynamic alteration indicated a hemodynamic maladjustment with a preferential constriction at RE. Treatment consists of multidrugs, namely angiotensin converting enzyme inhibitor, calcium channel blocker, antiplatelet and anticoagulant, with or without angiotensin II receptor antagonist. Following the treatment, correction of hemodynamic maladjustment has been achieved which is characterized by reductions in RE 6046 +/- 2191 dyne x s x cm(-5), PG 52 +/- mm Hg, FF 0.19 +/- 0.1 and increments in RPF 341 +/- 118 mL/min/1.73 m2, PTCF 280 +/- 106 mL/min/1.73 m2 and GFR 64 +/- 17 mL/min/1.73 m2. Coinciding with hemodynamic improvement, there has been a steadily increased creatinine clearance and improvement in FE Mg 4.3 +/- 2.6% and suppression of proteinuria 0.29 +/- 0.4 g/24 h after the period of follow-up of greater than 10 years.

A dysfunctioning glomerular endothelium was demonstrated in chronic kidney disease (CKD) patients by means of in vitro endothelial cell cytotoxicity test and of in vivo intrarenal hemodynamic study. An enhanced endothelial cell cytotoxicity in CKD patients was 26.5 +/- 12% as compared to 0.4 +/- 1% of control. An altered intrarenal hemodynamics revealed 1) a reduction in renal plasma flow, 190 +/- 67 mL/min/1.73 m2 versus control 595 +/- 45 mL/min/1.73 m2, and in peritubular capillary flow, 149 +/- 55 mL/min/1.73 m2 versus control 479 +/- 46 mL/min/1.73 m2, 2) an elevated intraglomerular hydrostatic pressure, 55 +/- 2 mmHg versus control 51 mmHg, elevated afferent arteriolar resistance, 13184 dyne x s x cm(-5) versus control 2443 +/- 154 dyne x s x cm(5), and elevated efferent arteriolar resistance, 13591 +/- 7591 dyne x s x cm(-5) versus control 3062 +/- 177 dyne x s x cm(-5). Both enhanced endothelial cell cytotoxicity and altered intrarenal hemodynamics reflect glomerular endothelial dysfunction which is likely responsible for the renal disease progression in CKD.

Hemodynamic maladjustment with predominant constriction at the efferent arteriole has been encountered in a variety of clinical settings of glomerulonephropathy. In essence, it induces not only intraglomerular hypertension but also exaggeratedly reduces the peritubular capillary flow, which supplies the tubulointerstitial compartment. The hemodynamic maladjustment is believed to reflect a glomerular endothelial cell dysfunction. In this regard, oxidative stress and antioxidant defect are likely responsible for the glomerular endothelial dysfunction. Improvement in renal function was accomplished following the correction of oxidant and antioxidant imbalance with antioxidant therapy and vasodilators. Following such therapy, there was a correction in hemodynamic maladjustment with a decline in intraglomerular hydrostatic pressure and an increase in renal perfusion with a subsequent increase in renal functions namely creatinine clearance, glomerular filtration rate and a decline in FEMg.

The spatial relationship between renal perfusion and nephronal structure was determined in 51 nephrotic patients consisting of 11 patients with steroid sensitive, minimal change (MC) nephrosis, 12 patients with steroid resistant, mesangial proliferative (MesP) nephrosis and without tubulointerstitial fibrosis (TIF), 11 patients with steroid resistant, MesP nephrosis and with low grade TIF and 17 patients with focal segmental glomerulosclerosis (FSGS). The intrarenal hemodynamic study revealed a unique correlation between renal perfusion and nephronal structure. A normal or slight reduction in peritubular capillary flow observed in MC or mild MesP nephrosis correlates with an intact tubulointerstitial structure. A moderate reduction in peritubular capillary flow observed in steroid resistant, MesP nephrosis induces a low incidence of TIF. A severe reduction in peritubular capillary flow denotes a higher incidence of TIF as that observed in nephrosis with FSGS. Thus, it is of notion that the reduction in renal perfusion precedes the development of tubulo-interstitial fibrosis and thereby supports the concept of renal perfusion as a crucial determinant of nephronal structure.

Background. A progressive reduction in peritubular capillary flow is observed in chronic kidney disease (CKD) patients as the disease severity progresses. This suggests an altered vascular homeostasis in CKD patients, but such a defective mechanism needs to be verified. Methods. To study the vascular injury as reflected by circulating endothelial cell (CEC), the balance between angiogenic factor, vascular endothelial growth factor (VEGF), and antiangiogenic factor, endostatin. Results. A deficient VEGF was observed, whereas the value of endostatin and CEC were abnormally elevated in CKD patients. Discussion. Enhanced CEC reflects an increased activity of vascular injury. A deficient VEGF in the presence of enhanced antiangiogenesis (endostatin) implies a defective angiogenesis. This may explain the progressive nature of renal microvascular disease observed in late stage of CKD patients.

Eight patients between the ages of 5 and 26 years developed a rapid decline of renal function with a period of oliguria or anuria which ranged between 1 and 21 days. The initial assessment of renal function revealed a severe degree of glomerular, tubular, and vascular abnormalities. The magnitude of the renal dysfunction was quantified and expressed in terms of a clinical score. The degree of glomerular and tubular dysfunction was inversely proportional to the renal plasma flow and peritubular capillary blood flow, respectively. Similar findings have been observed in a variety of other glomerulonephropathies where a relationship exists between the reduction of peritubular capillary blood flow and the severity of the tubulointerstitial disease. Evidence to support the position that the reduction of peritubular capillary blood flow plays a primary role in inducing tubulointerstitial disease is as follows: (i) A reduction of peritubular capillary blood flow has been documented in mesangial proliferative nephrosis with steroid resistance prior to the detection of tubulointerstitial disease. (ii) Ischemic insults are capable of inducing tubulointerstitial disease in the experimental setting of renal artery occlusion in animals. (iii) As demonstrated in the present report, an improvement of tubular function can be achieved following an increase in peritubular capillary blood flow with therapy designed to enhance renal perfusion.

Enhanced circulating endothelial cells, elevated transforming growth factor beta, and depleted vascular endothelial growth factor were observed in nephrosis associated with focal segmental glomerulosclerosis (FSGS). Increased endothelial cell loss may be due to the elevated transforming growth factor beta, which can induce apoptosis of podocyte as well as tubular epithelium. Such injury may explain the depletion of vascular endothelial growth factor and increased endothelial cell loss in these patients. There biomarkers may have relevance to the altered intrarenal hemodynamics commonly observed in FSGS nephrosis.

Summary: Fourteen cases of severe steroid-resistant nephrosis with focal segmental glomerulosclerosis were identified by the moderate to severe impairment of glomerular function. Symptoms included low glomerular filtration rate, ultrafiltration coefficient and increased intraglomerular hydrostatic pressure, tubular dysfunction including a defect in transporting solute, which was reflected by increasing fractional excretion of filtered solutes, in concentrating and acidifying the urine, and vascular dysfunction including marked elevation of renal arteriolar resistances and inversely severe reduction of renal plasma flow and peritubular capillary blood flow. Of these 14 nephrotics, eight patients were randomly treated with prednisolone, cyclophosphamide and antihypertensive agents, namely reserpine, hydralazine or prazosin, and the other six patients who had previously been resistant to prednisolone and cyclophosphamide were treated with an enhanced-renal-perfusion formula that consisted of a combination of antiplatelet agents, calcium channel blockers, angiotensin-converting-enzyme inhibitors, anticoagulant and prednisolone. After follow-up of 62 months, all eight patients were refractory to the conventional treatment, showing persistent proteinuria with a progressive deterioration of renal function entering end-stage renal disease. In contrast, five of the six patients under the enhanced-renal-perfusion formula gradually improved their renal functions and survived after 82 months of follow-up. the remaining patient, who did not improve, died of sepsis.

Diabetic nephropathy (DN) has been regarded as a non-restorative chronic kidney disease (CKD) under current concept of practice. The current definition of CKD and the conventional diagnostic markers such as serum creatinine or microalbuminuria unfortunately limit them to CKD stage 3. Treatment initiated at this late stage fails to restore renal function, but simply slows the renal disease progression toward end-stage renal disease dependant to renal replacement therapy. Recent study on vascular homeostasis in late stage DN reveals (1) defective angiogenic factors associated with an impaired nitric oxide production which explains the therapeutic resistance to vasodilator treatment. (2) abnormally elevated anti-angiogenic factors associated with a progressive reduction in peritubular capillary flow and a progressive decline in renal function. In contrast to the above observation, DN would become restorative if it would be recognized and treated at an early stage during normoalbuminuria (CKD stages 1,2) under which the vascular homeostasis is adequately functional. ACEI and ARB combination can enhance peritubular capillary flow, correct the chronic renal ischemia and therefore restore renal function. This innovative therapeutic strategy can effectively prevent the end-stage renal disease in DN.

Circulating toxins namely: free radicals, cytokines and metabolic products induce glomerular endothelial dysfunction, hemodynamic maladjustment and chronic ischemic state;this leads to tubulointerstitial fibrosis in chronic kidney disease (CKD). Altered vascular homeostasis observed in late stage CKD revealed defective angiogenesis and impaired nitric oxide production explaining therapeutic resistance to vasodilator treatment in late stage CKD. Under current practice, CKD patients are diagnosed and treated at a rather late stage due to the lack of sensitivity of the diagnostic markers available. This suggests the need for an alternative therapeutic strategy implementing the therapeutic approach at an early stage. This view is supported by the normal or mildly impaired vascular homeostasis observed in early stage CKD. Treatment at this early stage can potentially enhance renal perfusion, correct the renal ischemic state and restore renal function. Thus, this alternative therapeutic approach would effectively prevent end-stage renal disease.

Renal microvascular disease reflected directly by peritubular capillary flow reduction and indirectly by renal function impairment has been documented in early diabetic nephropathy (DN) associated with normoalbuminuria and normal serum creatinine concentration. The renal microvascular disease observed in early DN [chronic kidney disease (CKD) stages 1-2] could progress under current practice to late DN (CKD stages 3-5) with a further reduction in peritubular capillary flow. This advanced renal microvascular disease in late DN is characterized by therapeutic resistance to vasodilators and altered vascular homeostasis associated with impaired nitric oxide production. The renal microvascular disease is progressive as the disease severity progresses and eventually induces chronic renal ischemia and a progressive tubulointerstitial fibrosis. Further study has revealed that early DN is associated with an adequately functional vascular homeostasis. Therefore, recognition and treatment of early renal microvascular disease at early DN (stages 1-2) could enhance renal perfusion and restore renal function.

Microalbuminuria (amount greater than 30-300 mg/day) reflects an abnormal glomerular capillary permeability to protein. It is usually dependent upon three mechanisms. First, loss of negatively charged surface of the glomerular capillary wall secondary to circulating toxic substances injury-namely, oxidative stress and proinflammatory cytokines-allows the albumin with negatively charged surface to freely escape into the urine. Second, intraglomerular hypertension and hemodynamic maladjustment secondary to glomerular endothelial dysfunction increases filtration pressure and enhances sized selective proteinuria leakage. Third, podocyte injury leads to a vicious cycle of hemodynamic maladjustment and endothelial and podocyte injuries. All three of these mechanisms induce glomerular endothelial injury and microalbuminuria, which reflects renal microvascular disease.

Current treatments of chronic kidney disease (CKD) patients frequently result in progressive decline in renal perfusion, leading to the end-stage renal disease. Such renal failures may be a reflection of the progressive nature of renal microvascular disease. The aim of the present study is to elucidate the mechanism of microvascular homeostasis in CKD patients with moderately impaired renal function. We determined biomarkers relevant to vascular homeostasis, such as circulating endothelial cell (CEC), and biomarkers of vascular repair, such as vascular endothelial growth factor (VEGF), angiopoietin-1, tie-2, angiopoietin-2 and VEGF-R2. The present result revealed an enhanced vascular injury which was reflected by increased number of circulating endothelial cells. In addition, a defective vascular repair was also reflected by deficiencies in angiogenic factors such as VEGF, and angiopoietin-1, whereas the anti-angiogenic factors such as angiopoietin-2 and VEGF-R2 were elevated. In conclusion, the activity against vascular injuries increased under the presence of defective ability of vascular repair in CKD with moderately impaired renal function. This finding may explain the present therapeutic failure in treating these CKD patients, and imply that treatment at an earlier stage of CKD should be implemented.

This study was aimed to evaluate the combined effect of curcumin with vitamin C supplementation on hyperglycemic and dyslipidemia conditions and endothelial cell dysfunction induced in diabetic rats. Wistar Furth rats were used and divided into four groups: control (single injection of 0.9% sterile saline), STZ (streptozotocin, Sigma, 55 mg/kg.BW, i.v.), STZ-vitC (1 g/l ascorbic acid mixed in drinking water), STZ-cur (daily oral treatment of 300 mg/kg.BW curcumin; Cayman Chemical Co., USA), and STZ-cur+vitC (1 g/l ascorbic acid mixed in drinking water and oral treatment of 300 mg/kg.BW curcumin). On 8th week after STZ-injection, the microcirculation in the iris tissue was observed using intravital fluorescence videomicroscopy, and also leukocyte adhesion in the venule was examined for each group. Blood glucose (BG), lipid profiles, glycosylated hemoglobin (HbA1c) were measured in blood samples collected at the end of each experiment. The contents of liver malondialdehyde (MDA) were also quantified for each group. Feeding curcumin (STZ-cur) could decrease BG, HbA1c, dyslipidemia, and MDA significantly, compared to STZ. In cases of feedings curcumin with vitamin C, these results were more effective in all aspects, including leukocyte adhesion. In conclusion, curcumin might increase the effect of vitamin C in protecting the function of endothelial cells through its anti-oxidant with hypoglycemic and hypolipidemic actions.

This paper was aimed to investigate (1) the early marker of endothelial injury in type 2 diabetes, (2) the intrarenal hemodynamics and renal function, and (3) the therapeutic strategy aiming to restore renal function. Fifty patients (35 normoalbuminuric and 15 albuminuric type 2 diabetes) were examined. Blood was collected for determination of circulating vascular endothelial cells (CEC) and the serum was prepared for determination of transforming growth factor beta (TGFbeta), ratio of CEC/TGFbeta, and soluble vascular cell adhesion molecule. Intrarenal hemodynamics and renal function were also assessed. The results showed that increased number of circulating EC, elevated TGFbeta and depleted ratio of CEC/TGFbeta were significantly observed. Intrarenal hemodynamic study revealed a hemodynamic maladjustment characterized by preferential constriction of the efferent arteriole, intraglomerular hypertension and reduction in peritubular capillary flow. It was concluded that early marker of endothelial injury is reflected by increasing number of CEC. Such markers correlate with the glomerular endothelial dysfunction associated with hemodynamic maladjustment. Early detection of endothelial injury and appropriate correction of hemodynamic maladjustment by multidrug vasodilators can effectively restore renal function in type 2 diabetic nephropathy.

This paper was aimed to study biomarkers of endothelial injury in chronic kidney diseases. Fifty chronic kidney disease patients were subject to the following determinations: (i) circulating endothelial cells, (ii) soluble VCAM-1, (iii) transforming growth factor beta (TGFB), and (iv) intrarenal hemodynamics. Increased number of circulating endothelial cells was significantly observed. A significant depletion of vascular endothelial growth factor (VEGF) or a depleted VEGF/TGFB ratio was also documented. Results showed that sVCAM was not significantly different from normal control. Intrarenal hemodynamic alteration demonstrated a characteristic of hemodynamic maladjustment. Since increased number of circulating endothelial cells is a sensitive biomarker for endothelial cell injury in chronic kidney diseases, such injury is supported by the depletion of VEGF. The endothelial cell loss correlates with the glomerular endothelial dysfunction characterized by hemodynamic maladjustment at the efferent arteriole and reduction in peritubular capillary flow. In conclusion, correction of such hemodynamic maladjustment with multidrug vasodilators can effectively restore renal function in chronic kidney diseases.

Altered renal function has been encountered in normoalbuminuric patient with type 2 diabetes. A search for alternative index that is more sensitive than microalbuminuria for early detection of diabetic nephropathy has been performed. In the present paper, compartmental functions of nephron namely creatinine clearance (CCr) reflecting glomerular function, fractional excretion of magnesium (FE Mg) reflecting tubular function and intrarenal hemodynamics reflecting vascular function were assessed in 40 type 2 diabetic patients with normoalbuminuria and in 10 type 2 diabetic patients with albuminuria. In normoalbuminuric patients, glomerular function showed a low, normal or high CCr due to hyperfiltration. Tubular function revealed a significantly elevated FE Mg. Vascular function was altered with preferential constriction of the efferent arteriole, intraglomerular hypertension and profound reduction in peritubular capillary flow. A greater degree of functional defect was observed in albuminuric patients. Defective functions of the nephron implies that renal tissue injury has already been present in normoalbuminuric state. FE Mg appears to be a sensitive marker for early detection of diabetic nephropathy. Significant reduction in peritubular capillary flow correlates inversely with the altered FE Mg. Such correlation favors the chronic ischemic concept of tubulointerstitial injury and therefore supports the tubular functional defect observed in type 2 diabetes.

Increased activated circulating endothelial cells, enhanced von Willebrand factor (vWF:Ag) and adhesion molecules (sVCAM-1) are observed in patients with beta-thalassemia/hemoglobin E. Such evidences of endothelial cell injury are associated with altered intrarenal hemodynamics with a significant reduction in renal plasma flow. Altered renal functions (namely depleted creatinine clearance) and abnormal tubular function test, which is reflected by abnormally increased fractional excretion of magnesium (FE Mg), are also delineated. The increased FE Mg implies tubulointerstitial injury which may relate to the microvascular endothelial injury and chronic ischemia.

A persistent proteinuria is commonly observed in nephrotic patient with focal segmental glomerulosclerosis (FSGS) under treatment with prednisolone+/-cyclophosphamide or with vasodilators (ACEI+AII receptor antagonist, calcium channel blocker and antiplatelet agent). Fourteen such patients with persistent proteinuria were subject to be treated with Ganoderma lucidum. Initial study revealed an enhanced endothelial cell cytotoxicity induced by patient's serum, and an altered immunocirculatory balance with predominant proinflammatory cytokine TNF alpha activity in the presence of defective anti-inflammatory cytokine interleukin-10. Treatment with Ganoderma lucidum suppressed endothelial cell cytotoxicity, restored immunocirculatory balance and successfully suppressed proteinuria in all of these 14 patients.

Due to the previously therapeutic failure in treating eleven focal segmental glomerulosis (FSGS) nephrotic patients (group I) with prednisolone, cyclophosphamide and antihypertensive agents (reserpine, hydralazine or prazosin) who all entered end-stage renal disease, we prospectively evaluate 18 FSGS nephrotic patients who have been treated with combined formula consisting of ACEI, AIIRA, CCB, antiplatelet+/-heparin; group II. All the patients were subject to renal function studies namely creatinine clearance, fractional excretion of magnesium (FE Mg) and intrarenal hemodynamics. Treatment outcome of patients in group II was comparatively assessed before and after therapy. Clinical profiles were comparatively matched between groups I and II. The intrarenal hemodynamic study in all nephrotic patients revealed hemodynamic maladjustment characterized by preferential constriction at the efferent arteriole. Such constriction induced intraglomerular hypertension and exaggeratedly reduced peritubular capillary flow (PTCF). Following treatment with combined formula (group II), reductions in efferent arteriolar resistance and intraglomerular hydrostatic pressure were observed in conjunction with the increases in PTCF and glomerular filtration rate in all 18 patients. Correction of hemodynamic maladjustment with combined formula effectively restores renal function and thereby prevents the renal disease progression in FSGS nephrosis.

Glomerular endothelial cell dysfunction (GED) with defective release of vasodilator has been delineated in nephrosis (NS) in vivo and in vitro studies. In NS with focal segmental glomerulosclerosis (FSGS), an immunocirculatory balance may be impaired due to defective anti-inflammatory cytokine. This study aimed at simultaneous determination of both proinflammatory cytokine (tumor necrosis factor alpha) and an anti-inflammatory cytokine (interleukin-10) in NS with FSGS. An endothelial cell cytotoxicity (ECC) was also examined using nephrotic serum. It was shown that (1) the initial endothelial cell cytotoxicity was significantly different from the control, (2) ratio between tumor necrosis alpha and interleukin-10 was significantly elevated, and (3) intrarenal hemodynamics was changed significantly.

Glomerular endothelial cell (GEC) dysfunction due to oxidative stress and enhanced proinflammatory cytokines plays an important role in inducing proteinuria and procoagulant activity, namely blood hypercoagulability, hyperviscosity and local intravascular coagulation and altered hemorheology in NS. A dysfunctioning GEC releases fewer endothelium-dependent vasodilators but produces more vasoconstrictors. Severe intrarenal hemodynamic alteration associated with hemodynamic maladjustment with preferential constriction at the efferent arteriole has been uniquely implicated in severe GN and NS-FSGS. Such a constriction exerts three significant hemodynamic impacts. Proximal to the efferent arteriolar constriction, it induces (i) an overestimated GFR due to hyperfiltration and (ii) an elevated intraglomerular hydrostatic pressure. Distal to the efferent arteriolar constriction, it (iii) exaggeratedly reduces PTCF which correlates with the TIF.

Glomerular endothelial dysfunction is believed to be responsible for the proteinuria and nephronal damage, namely tubulointerstitial fibrosis and glomerulosclerosis, observed in severe nephrosis such as focal segmental glomerulosclerosis. A dysfunctioning glomerular endothelium is likely to be induced by oxidative stress and oxidized LDL as well as altered immunocirculatory balance with a defective anti-inflammatory pathway. A defective release of vasodilator inconjunction with enhanced production of angiotensin II induces hemodynamic maladjustment by preferential constriction at the efferent arteriole. Such a hemodynamic maladjustment exerts two significant hemodynamic impacts. Close to the efferent constriction, it induces intraglomerular hypertension and glomerulosclerosis. Far from the efferent constriction, it reduces peritubular capillary flow, which eventually leads to tubulointerstitial fibrosis. Treatment with a vasodilator improves the hemodynamic maladjustment but does not completely suppress proteinuria. A successful suppression of proteinuria is accomplished by using Ganoderma lucidum and vitamins C and E. The beneficial effect of Ganoderma lucidum appears to be multifactorial, including the modulation of immunocirculatory balance, antilipid, vasodilator, antiplatelet and improved hemorheology. Together with vitamins C and E, this helps to neutralize oxidative stress and suppress the toxic effect to the glomerular endothelial function.