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Scientist uses bone cell progenitors derived from human embryonic stem cells to grow compact bone tissue in quantities large enough to repair centimeter-sized defects

Dr. Darja Marolt, an Investigator at The New York Stem Cell Foundation (NYSCF) Laboratory, is lead author on a study showing that human embryonic stem cells can be used to grow bone tissue grafts for use in research and potential therapeutic application. Dr. Marolt conducted this research as a post-doctoral NYSCF –Druckenmiller Fellow at Columbia University in the laboratory of Dr. Gordana VunjakNovakovic.

The study, published in the early online edition of Proceedings of the National Academy of Sciences during the week of May 14th, is the first example of using bone cell progenitors derived from human embryonic stem cells to grow compact bone tissue in quantities large enough to repair centimeter-sized defects. When implanted in mice and studied over time, the implanted bone tissue supported blood vessel ingrowth, and continued development of normal bone structure, without demonstrating any incidence of tumor growth.

Dr. Marolt’s work is a significant step forward in using pluripotent stem cells to repair and replace bone tissue in patients. Bone replacement therapies are relevant in treating patients with a variety of conditions, including wounded military personnel, patients with birth defects, or patients who have suffered other traumatic injury. Since conducting this work as proof of principle at Columbia University, Dr. Marolt has continued to build upon this research as an Investigator in the NYSCF Laboratory, developing bone grafts from induced pluripotent stem (iPS) cells. iPS cells are similar to embryonic stem cells in that they can also give rise to nearly any type of cell in the body, but iPS cells are produced from adult cells and as such are individualized to each patient. By using iPS cells rather than embryonic stem cells to engineer tissue, Dr. Marolt hopes to develop personalized bone grafts that will avoid immune rejection and other implant complications.

The New York Stem Cell Foundation has supported Dr. Marolt’s research throughout her career, first through a NYSCF – Druckenmiller Fellowship to fund her post-doctoral work at Columbia University, and now with a NYSCF – Helmsley Investigator Award at The New York Stem Cell Foundation Laboratory. “The continuity of funding provided by NYSCF has allowed me to continue my research uninterrupted, making progress more quickly than would have otherwise been possible,” Dr. Marolt said.

Provided by New York Stem Cell Foundation

Abstract

Plasma beta-endorphin, prolactin (PRL), FSH and LH were measured in 17 volunteer male subjects at rest and under the stress caused by a long-distance nordic ski race. The race induced increased levels of beta-endorphin and PRL in all skiers. The changes in PRL with exercise were significantly related to the changes in beta-endorphin (r = 0.69, p less than 0.001). Furthermore, the highly trained skiers training over 150 km.week-1 of nordic ski showed consistently higher post-exercise beta-endorphin and PRL levels than the moderately trained skiers who trained for 20 km.week-1. In addition the race induced slight falls in FSH and LH; however plasma gonadotropin levels did not show any correlation with plasma beta-endorphin concentrations and did not differ between the two groups of skiers. These results suggest that endogenous opioid peptides may modulate PRL secretion in heavy exercise, since they are of minor importance in the release of FSH and LH in such a situation. The observations also suggest that the degree of previous training and the exercise intensity do seem to be responsible for the hormonal changes.

PMID:
2969335
[PubMed – indexed for MEDLINE]

Abstract

OBJECTIVE:

Intraarticular hyaluronic acid is indicated for patients with osteoarthritis of the knee. However, clinical experience, especially efficacy and adverse events, with repeated injection series in the long term are limited.

DESIGN:

Patients were referred to a large primary care center for management of osteoarthritis of the knee. All were naive to intraarticular hyaluronic acid therapy and met our entry criteria, including resting visual analog scale pain of > 45 mm, radiographic confirmation of unilateral knee grade 1-3 osteoarthritis, and willingness to receive intraarticular therapy. Patients received a three-intraarticular injection series with Suplasyn (10 mg/ml, 2-ml injection) over 3 wks. Patients were instructed to return for consideration of repeat injection series based on their perception of pain restricting daily activity and a resumption of severity similar to their initial presentation. This prospective naturalistic cohort was followed for 6.7 yrs. Patients completed baseline assessment of rest and walking visual analog scale pain (primary efficacy variable), completed a 5-point categorical global satisfaction score, and recorded adverse events and concomitant therapeutic modality use at each study visit. Patients returned for consideration of a repeat injection series based on their perception of symptom severity and were eligible if their resting visual analog scale pain was > 45 mm. The three-injection series and data collection were repeated, and again, patients were given similar instructions regarding consideration of a third injection series.

RESULTS:

Of 897 referral patients, 537 (mean age, 68 +/- 8 yrs; mean duration of symptoms, 7.4 +/- 4.1 yrs) met our criteria, and only 21 patients did not return for a second injection series. The mean time between first and second series was 27 +/- 7 wks. The change in walking visual analog scale pain was significantly improved from baseline after the first series (81.3%, P < 0.001) and second series (86.7%, P < 0.0001). Similarly, resting visual analog scale pain was significantly decreased from baseline after the first (P < 0.001) and second (P < 0.001) series, and patient satisfaction was significantly improved with each injection series (P < 0.03 and P < 0.01). Very few adverse events were recorded and were limited to local pain and swelling. Use of concomitant therapeutic modalities at presentation for a second injection series included: nonsteroidal anti-inflammatory drugs/cyclooxygenase-2 medications (37%), acetaminophen (31%), oral nutraceuticals (12%), and physical therapy and bracing (12%).

CONCLUSIONS:

Intraarticular hyaluronic acid injections were highly effective in improving resting and walking pain in patients with osteoarthritis of the knee on a first and a second treatment series. Duration of symptom control was about 6 mos, and the therapy was highly satisfactory to patients and was associated with very few local adverse events and limited use of concomitant therapeutic modalities. These data support the potential role of intraarticular hyaluronic acid as an effective long-term therapeutic option for patients with osteoarthritis of the knee.

PMID:
15785261
[PubMed – indexed for MEDLINE]

Abstract
Cerebrolysin is a drug consisting of low-molecular-weight neurotrophic peptides and free amino acids. Cerebrolysin has been shown to ameliorate the effects of oxidative stress, reduce apoptosis, and promote neuronal growth in several degenerative and acquired central nervous system insults, including dementias, stroke, and traumatic injuries. Little is known about its therapeutic efficacy in peripheral nervous system diseases. In this study, we clinically evaluated the effects of cerebrolysin on peripheral nervous system lesions. We evaluated the clinical efficacy of cerebrolysin in six patients with the following conditions who failed to respond to conventional therapies: (1) atonic bladder due to inflammatory radiculitis; (2) paraplegia due to inflammatory radiculoneuropathy; (3) post-traumatic brachial plexopathy; (4) compressive radial nerve injury; (5) post-traumatic facial nerve paralysis; and (6) diabetic ophthalmoplegia. Our results showed that cerebrolysin was more associated with rapid neurological recovery after various peripheral nerve lesions than other therapies including steroids and supportive therapies such as vitamins and antioxidants. The present results support the therapeutic efficacy of cerebrolysin in the treatment of acquired peripheral nervous system diseases.
Key Words: cerebrolysin; neurotrophic effect; neuroprotection; peripheral nervous system

FULL ARTICLE: www.superhumangear.com

 

Abstract

In an attempt to compare effects of different neurotrophic factors on impaired memory function, young adult naive rats were trained to find the hidden platform in the Morris water maze (3 consecutive days, eight trials/day). The fimbria-fornix was unilaterally removed by aspiration and nerve growth factor (NGF) (11 μg/ml and 0.5 μg/ml; groups NGF and ngf, respectively) or basic fibroblast growth factor (bFGF) (0.2 μg/ml, group FGF) were applied via intra-cerebroventricular infusion by the osmotic minipump (flow rate 0.5 μl/h, 14 days). Nootropic drug Cerebrolysin (EBEWE Arzneimittel; 2.5 ml/kg/day, group CER) was applied via intraperitoneal injection (14 days). One group was formed by the rats treated with NGF (11 μg/ml) and Cerebrolysin (group NGFCER). Non-lesioned and lesioned only rats served as controls (groups INT and LES). After a 14-day treatment, rats were tested using the retention test (1 day, four trials). On the next day, the rats were tested using transfer test (3 days, eight trials/day). Escape latency and length of trajectory was recorded. Groups NGF, ngf, FGF and LES were similarly impaired in their ability to retrieve the old position of the platform (retention test), as well as in their ability to navigate to the new position of the platform (transfer test). In the latter, NGF group significantly differed from lesioned animals. Groups CER and NGFCER were comparable to group INT in the retention or transfer test. It is concluded that anterograde amnesia elicited by fimbria-fornix lesion can be abbreviated by NGF and/or CER, while retrograde amnesia is absent only in rats treated by CER. No short-term influence of bFGF was found. It is suggested that biochemical systems other than the cholinergic one are involved.

Keywords

  • Central nervous system regeneration;
  • Nerve growth factor;
  • Basic fibroblast growth factor;
  • Cerebrolysin;
  • Fimbria-fornix lesion;
  • Spatial memory;
  • Retrograde and anterograde amnesia

BUY CHEAP TELMISARTAN

Abstract

Clinical trials have shown that angiotensin II receptor blockers reduce the new onset of diabetes in hypertensives; however, the underlying mechanisms remain unknown. We investigated the effects of telmisartan on peroxisome proliferator activated receptor γ (PPAR-δ) and the adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway in cultured myotubes, as well as on the running endurance of wild-type and PPAR-δ-deficient mice. Administration of telmisartan up-regulated levels of PPAR-δ and phospho-AMPKα in cultured myotubes. However, PPAR-δ gene deficiency completely abolished the telmisartan effect on phospho-AMPKαin vitro. Chronic administration of telmisartan remarkably prevented weight gain, enhanced running endurance and post-exercise oxygen consumption, and increased slow-twitch skeletal muscle fibres in wild-type mice, but these effects were absent in PPAR-δ-deficient mice. The mechanism is involved in PPAR-δ-mediated stimulation of the AMPK pathway. Compared to the control mice, phospho-AMPKα level in skeletal muscle was up-regulated in mice treated with telmisartan. In contrast, phospho-AMPKα expression in skeletal muscle was unchanged in PPAR-δ-deficient mice treated with telmisartan. These findings highlight the ability of telmisartan to improve skeletal muscle function, and they implicate PPAR-δ as a potential therapeutic target for the prevention of type 2 diabetes.

© 2011 The Authors Journal of Cellular and Molecular Medicine © 2011 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

PMID:
20477906
[PubMed – indexed for MEDLINE]

BUY CHEAP TELMISARTAN

Abstract

The World Antidoping Agency (WADA) has introduced some changes in the 2012 prohibited list. Among the leading innovations to the rules are that both 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (peroxisome proliferator-activated receptor-δ [PPAR-δ]-5′ adenosine monophosphate-activated protein kinase [AMPK] agonist) and GW1516 (PPAR-δ-agonist) are no longer categorized as gene doping substances in the new 2012 prohibited list but as metabolic modulators in the class “Hormone and metabolic modulators.” This may also be valid for the angotensin II receptor blocker telmisartan. It has recently been shown that telmisartan might induce similar biochemical, biological, and metabolic changes (e.g., mitochondrial biogenesis and changes in skeletal muscle fiber type) as those reported for the former call of substances. We suspect that metabolic modulators abuse such as telmisartan might become a tangible threat in sports and should be thereby targeted as an important antidoping issue. The 2012 WADA prohibited list does not provide telmisartan for a potential doping drug, but arguments supporting the consideration to include them among “metabolic modulators” are at hand.

PMID:
22130396
[PubMed – in process]

Abstract

Clinical interventions leading to improved survival in patients with acute myocardial infarction have, paradoxically, increased the need for cardiac regenerative strategies as more people are living with heart failure. Over the last 10-15 years there have been significant advances in our understanding of cell-based therapy for cardiac repair. Evidence that paracrine stimulation largely underlies the functional benefits in cell transplantation has led to a paradigm shift in regenerative medicine: from cell therapy to factor/protein-based therapy. Although, future regenerative approaches may likely involve a synergistic protein cocktail, this review will focus on the role of a promising candidate, thymosin beta 4 (Tβ4) in cardioprotection, neovascularization, tissue regeneration and inflammation – all essential components in cardiac repair.

PMID:
22236126
[PubMed – in process]

Abstract

OBJECTIVES:

We sought to examine the effect of atorvastatin therapy on exercise leg blood flow in healthy middle-aged and older-men and women.

BACKGROUND:

The vasodilatory response to exercise decreases in humans with aging and disease and this reduction may contribute to reduced exercise capacity.

METHODS:

We used a double-blind, randomly assigned, placebo-controlled protocol to assess the effect of atorvastatin treatment on exercising leg hemodynamics. We measured femoral artery blood flow (FBF) using Doppler ultrasound and calculated femoral vascular conductance (FVC) from brachial mean arterial pressure (MAP) before and during single knee-extensor exercise in healthy adults (ages 40-71) before (PRE) and after (POST) 6 months of 80 mg atorvastatin (A: 14 men, 16 women) or placebo (P: 14 men, 22 women) treatment. FBF and FVC were normalized to exercise power output and estimated quadriceps muscle mass.

RESULTS:

Atorvastatin reduced LDL cholesterol by approximately 50%, but not in the placebo group (p < 0.01). Atorvastatin also increased exercise FBF from 44.2 ± 19.0 to 51.4 ± 22.0 mL/min/W/kg muscle whereas FBF in the placebo group was unchanged (40.1 ± 16.0 vs. 39.5 ± 16.1) (p < 0.01). FVC also increased with atorvastatin from 0.5 ± 0.2 to 0.6 ± 0.2 mL/min/mmHg/W/kg muscle, but not in the placebo subjects (P: 0.4 ± 0.2 vs. 0.4 ± 0.2) (p < 0.01).

CONCLUSIONS:

High-dose atorvastatin augments exercising leg hyperemia. Statins may mitigate reductions in the exercise vasodilatory response in humans that are associated with aging and disease.

Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

PMID:
22018642
[PubMed – in process]

Influence of reduced glutathione infusion on glucose metabolism in patients with non-insulin-dependent diabetes mellitus

Abstract

To evaluate the relationship between oxidative stress and glucose metabolism, insulin sensitivity and intraerythrocytic reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio were measured in 10 non-insulin-dependent diabetes mellitus (NIDDM) patients and 10 healthy subjects before and after the intravenous administration of GSH. In particular, after baseline insulin sensitivity was assessed by a 2-hour euglycemic hyperinsulinemic clamp, either glutathione (1.35 g x m2 x min(-1)) or placebo (saline) were infused over a period of 1 hour. The same protocol was repeated at a 1-week interval, in cross-over, according to a randomized, single-blind design. In healthy subjects, baseline intraerythrocytic GSH/GSSG ratio (P < .0005) and total glucose uptake (P < .005) were significantly higher than in NIDDM patients. In the same subjects, GSH infusion significantly increased total glucose uptake (from 37.1 +/- 6.7 micromol kg(-1) x min(-1) to 39.5 +/- 7.7 micromol x kg(-1) x min(-1), P < .05), whereas saline infusion was completely ineffective. In addition, the mean intraerythrocytic GSH/GSSG ratio significantly increased after GSH infusion (from 21.0 +/- 0.9 to 24.7 +/- 1.3, P < .05). Similar findings were found in diabetic patients, in whom GSH infusion significantly increased both total glucose uptake (from 25.3 +/- 9.0 micromol x kg(-1) x min(-1) to 31.4 +/- 10.0 micromol x kg(-1) x min(-1), P < .001) and intraerythrocytic GSH/GSSG ratio (from 14.8 +/- 4.1 to 21.7 +/- 6.7, P < .01). Pooling diabetic patients and controls, significant correlations were found between intraerythrocytic GSH/GSSG ratio and total glucose uptake (r = .425, P < .05), as well as between increments of the same variables after GSH infusion (r = .518, P < .05). In conclusion, our data support the hypothesis that abnormal intracellular GSH redox status plays an important role in reducing insulin sensitivity in NIDDM patients. Accordingly, intravenous GSH infusion significantly increased both intraerythrocytic GSH/GSSG ratio and total glucose uptake in the same patients.

PMID:
9711998
[PubMed – indexed for MEDLINE]