Results Mitochondrial activity The mitochondrial activity of hMSCs exposed to epinephrine or vasopressin for 40 min was not significantly lower than the activity of cells in the control group when measured 1 h, 24 h, and 7 days after exposure (Figure 1). Apoptosis rate To assess apoptosis, we measured levels of caspase-3 and PARP-1 at 1 h, 24 h, and 7 d. A significantly (p < 0.05 - 0.001) higher level of PARP-1 was found in hMSCs 24 h and 7 d after exposure to vasopressin (Figures 2 and 3) and 7 d after exposure to epinephrine (Figure 3). A significantly (p < 0.001) higher level of caspase-3 was found only 24 h after exposure to epinephrine (Figure 4). Discussion Controlling intraoperative bleeding during knee or shoulder arthroscopic …show more content…
procedures is challenging. Intra-articular irrigation of local hemostasis agents is regularly used to safely and effectively control intraoperative bleeding in arthroscopy.1, 16, 17 Previous studies have evaluated the impact of local hemostasis on visualization of the surgical field or the cytotoxicity of local anesthetics on hMSCs and chondrocytes.5, 8, 13, 20, 22 This study is the first to examine the effects of epinephrine and vasopressin on HMSCs. hMSCs are pluripotent cells found in multiple human adult tissues, including bone marrow, synovial tissues, and adipose tissues.
They are derived from the mesoderm and they differentiate into bone, cartilage, muscle, and adipose tissue.21, 25 hMSCs are important in natural tissue regeneration processes: during the proliferative and remodeling phases, they migrate to the defected area and differentiate to replace cartilage.25 As such, adult mesenchymal stem cells have obtained great acceptance in the field of cartilage regeneration. Because of the critical role of stem cells in the complex process of cartilage reconstruction, we examined and evaluated whether common hemostasis agents used intra-articularly affect hMSCs. To date, studies have focused only on the efficacy of these medications for hemostasis and the effects on the operative visual field. We chose epinephrine as the hemostasis agent because it improves operative field clearance and is a commonly used medicine.1, 16, 17 Vasopressin has been used as a vasopressor with favorable outcomes,14, 15, 18, 19, 23 but, until now, it has been never been used in …show more content…
arthroscopy. Our most important finding is that neither epinephrine nor vasopressin have detrimental effects on the proliferation of hMSCs. The cells did show increasing apoptosis over time after exposure to the drugs. We quantified mitochondrial activity to determine stem cell viability, and we evaluated levels of apoptosis markers such as caspase-3 and PARP-1 to determine drug-induced initiation of apoptosis.21 We did not note any significant decreases in mitochondrial activity in hMSCs exposed to vasopressin or epinephrine at any time point studied compared to activity in the control group. PARP-1 was a significant marker of apoptosis 24 h and 7 d after exposure to vasopressin and 7 d after exposure to epinephrine. Caspase-3, another marker of apoptosis, significantly increased 1 d after exposure to epinephrine, but there were no increases in caspase-3 7 d after epinephrine exposure. This can be explained by changes in intracellular calcium dysregulation that lead to caspase-independent mechanisms of cell death.6, 10, 12 The results of our study demonstrate that 40 min of exposure to either vasopressin or epinephrine in vitro does not decrease stem cell mitochondrial activity. PARP-1 increased in cells exposed to vasopressin after 24 h and 7 d; PARP-1 increased in cells exposed to epinephrine only after 7 d. There are some limitations to our study that must be considered.
First, this in vitro model does not represent intraoperative intra-articular conditions such as bleeding, active blood supply, cell metabolic activities, or amount of synovial fluid. Also, because it is an in vitro model, our observations cannot necessarily be extrapolated to in vivo conditions. Still, the standardized in vitro conditions allow for the reproducibility of results related to substance-specific effects on cell viability, metabolic activity, and induction of apoptosis. The effects of intra-articular exposure to epinephrine and vasopressin on hMSCs require additional investigation. Further studies need to be performed to evaluate these effects closer to the cell membrane. Specifically, the expression of inducible nitric oxide synthase, which rapidly synthesizes large quantities of nitric oxide (a free radical), could be determined. An overproduction of nitric oxide causes damage to cellular components such as lipids, which decreases physiological function and leads to cell death.3,24 Additionally, our results should be confirmed in an animal
model. In conclusion, our findings suggest that epinephrine and vasopressin have varying time-dependent effects on apoptosis in hMSCs in vitro. Because of the increase in apoptosis rate without the decrease mitochondrial activity, the levels of toxicity remain unclear. Further studies are needed to evaluate the effects on hMSCs and translate the results into clinical practice. This in vitro study suggests that both epinephrine and vasopressin are potentially toxic drugs for intra-articular application during arthroscopic procedures such as bone marrow stimulation (e.g. microfracture) or rotator cuff repair.
Over a three week period a test subject was instructed to come to the exercise physiology lab once a week. The purpose of the first week was to determine the baseline test data for the participant. During this first week, the subject was asked how many hours of sleep they had gotten the night before and how much they weighed. The subject was then instructed to put on a heart monitor and wear an O2 apparatus and begin running on a treadmill. This treadmill was set at zero incline for the beginning of the run until three minutes had passed. At the three minute mark the incline increased by 2.5%. After this the incline was continuously increased by 2.5% every two minutes. During this process, the VO2 and RER exchange rate of the subject was being tracked through the O2 apparatus. Their heart rate was recorded every 15 seconds. In addition, the subject was asked their perceived exertion at every increase in incline. The subject continued to run until they could not run anymore, at this time they would hop off the treadmill.
Montaner, B. and Perez-Tomas, R. 2001. Prodigiosin-induced apoptosis in human colon cancer cells. Life sciences, 68 (17), p. 2025-2036.
The controlled group was left with 0 nicotine applied. The 4 treatment groups were treated with 4 different levels of nicotine concentrations: 25 µm, 50 µm, 75 µm, and a 100 µm. The treatment concentrations were applied on top of the pond drop that the Daphnia Magna’s were trapped in on the depression slide; a minute was given for Daphnia Magna acclimation with the treatments. Then, the heart rate of each of the 3 Daphnia Magna’s in the 5 groups was measured, 3 Daphnia Magna’s were tested in each group to attain the mean so that more accurate results were reached. The technique used was that we counted the number of heartbeats in a 10 second interval and then multiplied that number by 6 to attain Beats/min; an initial (before treatment) HBR and after treatment HBR were recorded for each Daphnia Magna. The raw data were written down in a table and were later moved for demonstration on a graph for the final preview. The data collected matched the expectations, for the controlled group: the heart beat rate was dropping slightly (becoming slower), the reason behind that was most likely the cooling chamber because there was no treatment applied or any other external
Also, we learned that depressants decrease the heart rate because they influence the parasympathetic nervous system which responsible for the rest and digest and depress the sympathetic nervous system (Silverthorn, 2010). The main stimulator in Red Bull is caffeine, it functions by blocking the effects of the adenosine, a brain chemical involved in sleep. When caffeine blocks adenosine, it causes firing of neurons that stimulate the sympathetic system, that triggers "fight or flight" response by releasing adrenaline. Adrenaline is a hormone that increases the heart rate and dilate the eye; another effect of Caffeine is changing the levels of dopamine, responsible for pleasure in the brain (Kollmorgen, 2011). We will be comparing the components individually to the baseline, we will also be testing the components in combination compared to their results individually and baseline. Our baseline will be aged tap
Every day we use our skeletal muscle to do simple task and without skeletal muscles, we will not be able to do anything. Szent-Gyorgyi (2011) muscle tissue contraction in rabbit’s muscles and discovered that ATP is a source for muscle contraction and not ADP. He proposed a mechanism to cellular respiration and was later used by Sir Hans Krebs to investigate the steps to glucose catabolism to make ATP. In this paper, I will be discussing the structure of muscle fibers and skeletal muscles, muscle contraction, biomechanics, and how glucose and fat are metabolized in the skeletal muscles.
The wide range of prospective uses for stem cells could greatly improve the health and wellbeing of many people. In stem cell treatments, undifferentiated cells are programmed to form specific cells, which can then be transplanted to the afflicted area. Stems cells can possibly treat afflictions including “Alzheimer’s diseases, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis” (“Stem Cell Basics”). Another important use is in drug testing. Drugs can be tested on stem cells that develop into the target tissue before using it on human test subjects, which improves safety. Finally, transplantation of organs created from stem cells could eliminate the need for human...
... (CNS) may also indicate another copper binding function for PrP. In blood and blood plasma, amino acids are mainly what copper binds to, yet the chief component which it actively binds to is Serum Albumin, which readily takes up 1 copper at its N terminal. The cerebrospinal fluid however, contains more amino acids and lacks a high quantity of serum albumin, and othe copper binding constituents normally found in blood. Thus it is hypothesised that PrP plays a role similar to albumin, by helping maintain copper homeostasis. Several studies have also shown that PrP opposes apoptosis reactions in some cells, by protecting the cells from the signals which would usually cause apoptosis to occur. Mutagenesis experiments have shown the PrP octarepeat domain is required to protect against Doppel-protein toxicity, which when usually expressed, would bring about cell death.
With ABC recipient site classification surgeons gain some insight in to regenerative potential of the surgical bed and can consider some modifications to help increasing of success rate of bone healing and decreasing morbidities of donor sites.
Mitochondria are organelles in cells that provide energy, and they have their own DNA. Sometimes, mitochondrial DNA has mutations in it, causing rare, deadly, and incurable diseases. Women who have defective mitochondria can pass these diseases onto their children, but mitochondrial replacement therapy allows these women to have healthy babies that are free from mitochondrial disease.
The second part of this lab was a computer simulation program to illustrate a frog’s electrocardiogram using various drugs in an isolated setting. The computer program entitled “Effects of Drugs on the Frog Heart” allowed experimental conditions to be set for specific drugs. The different drugs used were calcium, digitalis, pilocarpine, atropine, potassium, epinephrine, caffeine, and nicotine. Each of these drugs caused a different electrocardiogram and beats per minute reading. The calcium-magnesium ration affects “the permeability of the cell membrane”(Fox). When calcium is placed directly on the heart it results in three physiological functions. The force of the heart increases while the cardiac rate decreases. It also causes the appearance of “ectopic pacemakers in the ventricles, producing abnormal rhythms” (Fox). Digitalis’ affect on the heart is very similar to that of calcium. It inhibits the sodium-potassium pump activated by ATP that promotes the uptake of extracellular calcium by the heart. This in return strengthens myocardial contraction (Springhouse). Pilocarpine on the other hand
“An Examination of Animal Experiments.” Physician Committee for Responsible Medicine. N.p., n.d. Web. 13 Feb. 2014. .
Human development has drastically changed within the exercise and fitness industry since the 1940’s. This industry is now one of the largest, most studied, and sought out aspects of human life. Many people depend on exercise to sustain their health and change their bodies both physically and mentally. Specifically, many look to change their body composition, meaning how much muscular lean tissue and fat they have (Zanker, Cathy, and Louise). In many circumstances, such changes to one’s body are heavily scrutinized and evaluated against social norms (O’Donnell). Exercise to improve body composition can be done using two different methods, anaerobic and aerobic exercise. In regards to improving body composition, anaerobic exercise's effects are
Throughout the years, apoptosis has been thoroughly studied and investigated by millions of scientists around the world. Throughout people’s knowledge of cells, the cell cycle, mitosis and meiosis, and viruses, there are still questions that we ask. These questions can range from why doesn’t a human continue to grow when we produce millions of cells, what happens to cells that fail the mitosis and meiosis checkpoints, and what happens to the cells that are infected by viruses. The answer to these common and educational questions is all in the process known as apoptosis. Apoptosis is the death of cells that occurs as a normal and controlled part of an organism's growth or development. The common questions that people ask about the cell process
“With the exception of nutrition, more fallacies exist in the area of exercise than in any other area of health” (Dintiman, Stone, Pennington, & Davis, 1984). Exercise produces significant physical and mental benefits and is extremely vital to life. It substantially improves stamina, strengthens and tones muscles, helps prevent diseases, enhances flexibility, controls weight, and prolongs the quality of life. In order to gain all the benefits from exercise and be truly healthy, it is very important to understand and take action with both types of exercise: anaerobic and aerobic. With the combination of aerobic and anaerobic exercise, an individual will greatly increase their overall health and wellness significantly.
Regenerative medicine also seeks to understand the ability of a tissue or organ to repair itself. Many adult tissue contain stem cells but are at times not functional or is impaired by disease. Using factors to activate and promote instrinsic repair in a diseased organ opens up whole new prospect for therapies targeted toward many degenerative diseases.[9]