MK-677 vs. HGH | A Comprehensive Comparison

Scientists engaged in growth hormone-related research may be wondering about the comparative effectiveness and safety of MK-677 vs. hGH.

To address growing interest in this topic, we have created a guide for scientists looking to deepen their understanding of MK-677 versus hGH in the realm of growth hormone research.

In this comprehensive article, we provide a thorough analysis of both compounds, focusing on areas such as their:

• Impact on GH and IGF-1 levels
• Roles in muscle development and fat loss
• Potential for enhancing bone density

Moreover, we will delve into their distinct mechanisms of action, side effects, and safety considerations, offering a balanced view for scientific inquiry.

We also include guidance on where to source high-quality MK-677, which is likewise crucial to conducting reliable and valid research.

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What is MK-677?

MK-677, also known as ibutamoren, is a nonpeptide substance with a unique profile. Developed in the late 1990s by researchers at Merck & Co., its original purpose was to combat conditions like muscle wasting [1].

It has emerged as a potential solution to combating health issues related to growth hormone deficiency due to its ability to stimulate:

• The release of growth hormone (GH)
• The production of insulin-like growth factor 1 (IGF-1)

These mechanisms are crucial to the promotion of muscle growth and fat metabolism [2].

MK-677 belongs to a class of substances known as growth hormone secretagogues (GHS). It mimics the action of the hormone ghrelin, which is produced in the stomach and plays a vital role in regulating appetite and the distribution and rate of use of energy.

This enables MK-677 to bind to ghrelin receptors in the pituitary gland, a mechanism that leads to an increase in GH levels in the body. Studies have reported that a one-time dose of MK-677 can lead to a 55.6ng/ml peak in GH levels [3]. As a reference, physiological GH peaks usually reach up to 10-14ng/ml [4].

MK-677 particularly stands out as an orally active GHS thanks to its non-peptide structure. Unlike most GHSs, which have peptide structures and require injections for successful administration, MK-677 boasts an oral bioavailability of over 60% and a half-life exceeding 4-5 hours [2].

Current research into MK-677 is primarily focused on its potential as an oral therapy for growth hormone deficiency (GHD) [5]. It is also studied for its potential in various other conditions, including:

• Age-related muscle wasting
• Osteoporosis
• Sleep quality

Clinical studies have shown promising results in increasing lean body mass and bone mineral density. However, it is essential to note that MK-677 is not approved for any human use, and its application is limited to research settings [6].

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What is HGH?

Human growth hormone (hGH), also known as somatropin, refers to the synthetic version of growth hormone that is produced in the pituitary gland. The lab-created hormone, with a structure of 191 amino acids, is identical to its natural counterpart [7, 8].

It is produced using recombinant DNA technology, which replicates the human growth hormone sequence, and gives it the common name recombinant hGH (rhGH) [9].

rhGH was first developed by the American biotechnology company Genentech in 1981. Its primary purpose was to treat individuals with GHD, a condition where the body cannot produce sufficient growth hormone endogenously, leading to conditions like [10]:

• Stunted growth in children
• Metabolic complications in adults

The United States Food and Drug Administration (FDA) authorized recombinant hGH for medical use in 1985, marking a significant advancement in hGH therapy. This therapy is now FDA approved for several conditions in children and adults [10].

In children, hGH is officially authorized for therapy in the following indications:

• GHD
• Growth failure due to chronic renal insufficiency
• Noonan syndrome
• Prader-Willi syndrome
• Short bowel syndrome (SBS)
• Short stature homeobox (SHOX)-containing gene deficiency
• Small-for-gestational-age infants
• Turner syndrome

In adults, hGH is also FDA-approved for therapy in:

• GHD
• SBS
• Muscle wasting due to AIDS

Recombinant hGH therapy effectively increases serum growth hormone levels, addressing symptoms associated with GHD in both children and adults.

The medication, with a half-life of about 3.5 hours, is administered daily via injection, often before bedtime, to mimic natural growth hormone release [11].

In the United States and many countries around the world, hGH is a prescription-only medication and is not available over-the-counter.

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MK-677 vs. HGH | Comprehensive Comparison

Both hGH and MK-677 have been studied for their effects on serum GH, body composition, and various metabolic parameters in adults.

Here, we'll detail where the two compounds align and diverge, focusing on their research applications, safety profiles, and routes of administration:

• Administration: hGH must be injected due to its protein structure and sensitivity to digestion, whereas MK-677, with over 60% oral bioavailability, can be taken orally. Administering both in the evening aligns with natural GH release and may mitigate MK-677's appetite-increasing effects [2].
• Mechanism of action: hGH therapy raises GH levels even in those with a non-functioning pituitary gland, as it supplies the body with exogenous growth hormone. Conversely, MK-677 enhances GH production only if the pituitary gland remains functional.
• Half-life: MK-677 has a half-life of about 4-6 hours, sufficient to stimulate a prolonged increase in natural GH synthesis. On the other hand, hGH has a half-life of 3-4 hours, and serum GH remains elevated for up to 12 hours after injection. Thus, both compounds are suitable for once-daily administration [2, 11].
• Changes in serum GH levels: hGH results in a dose-dependent rise in serum GH levels, with high doses risking supraphysiological increases and side effects. In contrast, MK-677 stimulates natural GH synthesis that is subject to endogenous hormonal regulation, such as by somatostatin. Research indicates that MK-677 taken at 25mg/daily can lead to a 70% increase in pulsatile GH levels and a 97% increase in 24-hour mean GH levels [12].
• Changes in serum IGF-1 levels: Both hGH therapy and MK-677 can induce an increase in the levels of insulin-like growth factor-1 (IGF-1), which is the main anabolic mediator of GH's effects. According to research, administering MK-677 daily can lead to a 55% increase in IGF-1 levels at 2 weeks and 88% at 4 weeks [12, 13].

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Research Applications and Benefits of MK-677

Clinical researchers have investigated the range of effects of oral MK-677, including those arising from its activation of ghrelin receptors.

It is known that activation of the ghrelin receptors in the pituitary gland causes elevated GH levels, which can positively impact body composition, such as by increasing lean mass.

Activating the ghrelin receptors in the brain can have other effects, such as stimulating deep sleep and increasing appetite [14].

Here is a summary of key research findings related to MK-677:

• Lean Mass Gains: One study in 24 overweight young adults indicated that a daily intake of MK-677 25mg over an 8-week period resulted in significant muscle mass gain without any notable changes in fat mass. The study volunteers gained approximately +6.6lb in lean mass [15].
• Prevention of Muscle Loss: Another study involving eight healthy individuals demonstrated that MK-677 effectively reduces nitrogen loss during a calorie-deficient diet, thereby preventing muscle loss in conditions of weight loss [3].
• Improvement in Sleep Quality: In a study in eight participants given 25mg of MK-677 once nightly for two weeks, the subjects’ deep sleep increased by approximately 50%, along with a 20%+ rise in rapid-eye movement (REM) sleep [16].
• Reduction of LDL Cholesterol: A longitudinal trial in 65 healthy men and women that lasted over two years found that a daily MK-677 dose of 25mg substantially lowered LDL, also known as the “bad” cholesterol. This study recorded a 0.14mmol/l decrease in LDL in the MK-677 group, in contrast with a 0.12mmol/l increase in LDL with placebo [17].

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Research Applications and Benefits of HGH

hGH has been extensively researched and shown to be effective in addressing a wide variety of issues, including symptoms that may occur in GHD, such as muscle wasting and abdominal fat gain.

At doses between 0.2 to 1.2mg/daily, hGH therapy has been reported to [18]:

• Restore lean mass (up to 5% increase from pretreatment levels)
• Reduce abdominal fat (up to 10% reduction in adiposity from pretreatment levels)
• Slow osteoporosis development
• Reduce LDL by up to 16% from pretreatment levels
• Improve quality of life

However, hGH appears to have a considerably smaller impact on individuals with normal pituitary function. A meta-analysis of 31 trials in healthy volunteers reported that a mean daily dose of 0.014mg/kg body weight of hGH for an average duration of 26 weeks can result in [19]:

• A mean -4.6lb reduction in fat mass compared to placebo
• A mean +4.7lb increase in lean mass compared to placebo

There were no notable effects on bone mass or LDL levels. Trials in adults with muscle wasting disorders report that higher hGH doses (0.1mg/l) can lead to a greater increase in lean mass, namely +6.6lb greater than placebo [20].

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MK-677 Side Effects and Complications

While it lacks any sort of regulatory approval, MK-677 has undergone extensive clinical study, with the research available indicating that it is well-tolerated among study participants.

Nass et al. (2008), a trial in 65 healthy elderly patients that spanned two years, reported the following side effects with MK-677 at 25mg/daily [17]:

• Increased appetite (67%)
• Joint pain (58%)
• Swelling in the lower extremities (44%)
• Muscle discomfort (33%)

According to the study authors, these side effects were generally mild and tended to decrease after a few months into the trial.

In a separate study involving nine volunteers with GHD who were given higher MK-677 doses (50mg/daily), there were additional side effects noted, such as diarrhea and dry skin. Yet, these were deemed unlikely to be caused by the compound itself [21].

Since MK-677 is not authorized for human application, there is a lack of published specific contraindications.

Yet, researchers are advised to consider that MK-677’s effect on GH and IGF-1 levels can speed up the progression of cancers. For this reason, researchers studying MK-677 or other GHSs typically exclude subjects with malignancies from their studies.

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HGH Side Effects and Complications

Extensive clinical research has led the FDA to approve recombinant hGH for its effectiveness and safety in both children and adults with GH deficiency [22].

Moreover, this treatment has proven to be safe in adults not suffering from GHD when administered in physiological doses. The aforementioned meta-analysis of 31 RCTs identified the following hGH side effects and their incidence [19]:

• Swelling in the limbs: 50%
• Insulin resistance: 22%
• Joint discomfort: 21%
• Carpal tunnel syndrome: 19%

Most of these symptoms were related to temporary water retention and progressively decreased as participants adapted to the treatment [23].

These adverse reactions can be lessened by carefully adjusting the dosage, reducing it as needed, or stopping the treatment altogether.

It is important to recognize that hGH therapy is not advisable for those with untreated diabetes, a history of cancer, increased intracranial pressure, existing carpal tunnel syndrome, edema, or critical illness [24].

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Where to Buy MK-677 Online? | 2024 Edition

Qualified researchers interested in exploring the benefits of MK-677 should look for reputable vendors that offer US-made, third-party-tested reference materials.

Unfortunately, many online vendors of research peptides offer compounds of poor quality that may impede the success of an otherwise well-designed study.

This is why our team of experts has conducted a thorough investigation of the best MK-677 sources online, selecting two of the most trusted retailers in the research chemicals niche.

Chemyo

Chemyo is a well-established global vendor of research chemicals that is committed to providing compounds at fair prices. Here's why they stand out:

• US-Made MK-677: All Chemyo compounds are sourced in the United States. To ensure the quality and safety of their research chemicals, this vendor partners exclusively with certified manufacturers.
• Affordable Shipping: All U.S. orders over $100 and international orders over $275 ship free, helping drive down the cost of experimenting with MK-677.
• Excellent Customer Service: This vendor employs a customer service team that is highly responsive and readily available to address any inquiries.

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Limitless Life

Researchers looking for an alternative option will be pleased to know that Limitless Life also provides truly outstanding products and is committed to customer satisfaction. Here are some highlights about this vendor:

• Research-Grade Quality: Limitless Life relies on third-party lab testing to ensure that its MK-677 is of the highest purity and potency.
• Outstanding Customer Service: Their customer support staff are extremely helpful, always accessible, and prompt in responding to queries.
• VIP Club: Limitless Life has an exclusive VIP membership that offers discounts and early access to the latest research compounds.

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HGH vs. MK-677 | Verdict

MK-677 and hGH both show notabele anabolic effects like stimulating muscle growth, preventing muscle wasting, and increasing bone density.

Additionally, hGH is believed to aid in decreasing body fat, whereas MK-677 has been observed in clinical testing to promote deep sleep and lower LDL levels.

It is important to acknowledge that the effects and safety of MK-677 have not yet been thoroughly studied, necessitating caution when experimenting with the compound.

Qualified researchers interested in procuring MK-677 may legally obtain it from our top recommended vendor of research-grade compounds.

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