Bacterial protein synthesis; Microbial Metabolite; Bacterial HSV-1; Endogenous Metabolite

Oxytetracycline calcium is a key component of the bacterial aromatic polyketide family, a group of natural compounds with a variety of topologies. Oxytetracycline calcium is generated by type II polyketide synthase, which produces a poly-β-ketone backbone through consecutive decarboxylation condensation of malonyl-CoA extension units. The backbone is subsequently passed through cyclases, oxygenases, transferases, and other tailoring enzymes. Make adjustments [2].

The effects of calcium delivery of therapeutic dosages of oxytetracycline (82.8 mg/kg body weight to 1% body weight/day) for 10 days were species specific. Oxytetracycline calcium increases the relative liver weight of Morone chrysops For oxytetracycline calcium, the limits are 100 μg/kg in muscle and milk, 200 μg/kg in eggs, 300 μg/kg in liver and 600 μg/kg in kidneys. Oxytetracycline calcium is supplied to fish as medicated feed at dosages ranging from 35 to 75 mg ai kg-1 biomass on day 1 and continued for 7-14 days [1].

Oxytetracycline (OTC) is a broad-spectrum antibiotic that acts by inhibiting protein synthesis in bacteria. It is an important member of the bacterial aromatic polyketide family, which is a structurally diverse class of natural products. OTC is synthesized by a type II polyketide synthase that generates the poly-beta-ketone backbone through successive decarboxylative condensation of malonyl-CoA extender units, followed by modifications by cyclases, oxygenases, transferases, and additional tailoring enzymes. Genetic and biochemical studies have illuminated most of the steps involved in the biosynthesis of OTC, which is detailed here as a representative case study in type II polyketide biosynthesis[2].

Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg(-1)) and at higher doses (150, 300 mg kg(-1)) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose-response relationship. After 10 days of treatment at the recommended dose (75 mg kg(-1)), the mean value in muscle was 295 μg kg(-1). After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg(-1) OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg(-1). Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg(-1)) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg(-1) dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses.[1]

Absorption, Distribution and Excretion
Readily absorbed following oral administration.
SERUM HALF-LIFE ... IN HORSES IS ... 15.7 HR & 10.5 HR AFTER IV & IM INJECTIONS, RESPECTIVELY. ... /A FACTOR/ MAY BE THE INFLUENCE OF DOSE-DEPENDENT KINETICS ... .
The percentage of an oral dose that is absorbed (when the stomach is empty) ... for oxytetracycline /is/ 60 to 80% ... After a single oral dose, the peak plasma concn /of oxytetracycline/ is attained in 2 to 4 hr. /It has a half-life/ in the range of 6 to 12 hr and ... frequently admin 2 to 4 times daily ... The admin of 250 mg every 6 hr produces peak plasma concn of 2 to 2.5 ug/mL ... Increasing the dosage above 1 g every 6 hr does not produce significantly higher plasma concn ... Approx 10 to 35% of a dose of oxytetracycline is excreted in active form in urine, in which it is detectable within 30 min and reaches a peak concn about 5 hr after it is admin.
/Oxytetracycline is/ bound to plasma proteins ... approx ... 20-25%.
/Absorption is/ much less complete from lower ... tract ... Biliary concn ... /is/ 5 to 10 times higher than ... plasma. /Tetracyclines/
For more Absorption, Distribution and Excretion (Complete) data for OXYTETRACYCLINE (20 total), please visit the HSDB record page.

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Biological Half-Life
BIOLOGIC HALF-LIFE ... MAY BE 3-4 DAYS IN ANURIA.
The serum half-life of oxytetracycline is 6 to 10 hours in adults with normal renal function and is reported to be 47 to 66 hours in patients with severe renal impairment. In patients with normal renal function, approximately 60 to 70 percent of a single oral dose of oxytetracycline is excreted in urine within 72 hours as active drug.
A two-way crossover study was conducted in crossbred male calves (6-8 months old) to determine the bioavailability, pharmacokinetics and dosage regimens for a long-acting formulation of oxytetracycline (OTC-LA). The half-lives of oxytetracycline after intravenous and intramuscular administration were 7.8 hr and 24 hr, respectively. ....
The pharmacokinetic properties of oxytetracycline were studied following a single injection of a long-acting formulation (20 mg/kg body weight) into the semimembranosus muscle of healthy dogs and of dogs that had been experimentally infected with Ehrlichia canis. ... The mean apparent elimination half-life (t(1/2) beta) was significantly increased following infection. ... The absorption half-life (t(1/2) ab) was significantly decreased after infection.
SERUM HALF-LIFE ... IN HORSES IS ... 15.7 HR & 10.5 HR AFTER IV & IM INJECTIONS, RESPECTIVELY. ... /A FACTOR/ MAY BE THE INFLUENCE OF DOSE-DEPENDENT KINETICS ... .

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
A number of reviews have stated that tetracyclines are contraindicated during breastfeeding because of possible staining of infants' dental enamel or bone deposition of tetracyclines. However, a close examination of available literature indicates that there is not likely to be harm in short-term use of oxytetracycline during lactation because milk levels are low and absorption by the infant is inhibited by the calcium in breastmilk. Short-term use of oxytetracycline is acceptable in nursing mothers. As a theoretical precaution, avoid prolonged or repeat courses during nursing. Monitor the infant for rash and for possible effects on the gastrointestinal flora, such as diarrhea or candidiasis (thrush, diaper rash).
◉ Effects in Breastfed Infants
No adverse effects were noted in an unspecified number of breastfed infants whose mothers were taking oral oxytetracycline 1.5 or 2 grams daily for 3 days. Ages of the infants and extent of breastfeeding were not stated.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Interactions
SIMULTANEOUS ADMIN IRON AS FERROUS SULFATE REDUCED ABSORPTION & CAUSED SIGNIFICANT DECR IN SERUM CONCN OF ... OXYTETRACYCLINE ... IN MAN. ... MILK GIVEN SIMULTANEOUSLY REDUCED ABSORPTION OF ... OXYTETRACYCLINE BY ABOUT 50% ... .
INCR CONCN OF OXYTETRACYCLINE IN NASAL MUCUS DUE TO BROMHEXINE TREATMENT ... ATTRIBUTED TO EVAPORATION OF THE LESS VISCOUS MUCUS, ARISING FROM BROMHEXINE TREATMENT, RATHER THAN INCR MEMBRANE PERMEABILITY.
... OXYTETRACYCLINE MAY CAUSE UNPREDICTABLE FLUCTUATIONS IN BLOOD GLUCOSE LEVELS ... BY INCR HALF-LIFE OF INSULIN. ... ALSO ... WHEN OXYTETRACYCLINE & TOLBUTAMIDE ... USED CONCURRENTLY.
Striking antagonism between penicillin and tetracyclines has been observed clinically in pneumococcal meningitis ... /Tetracyclines/
For more Interactions (Complete) data for OXYTETRACYCLINE (10 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Swiss mice oral 7200 mg/kg /hydroxytetracycline monohydrochloride/

[1]. Transferability of oxytetracycline (OTC) from feed to carp muscle and evaluation of the antibiotic effects on antioxidant systems in liver and kidney. Fish Physiol Biochem, 2014.

[2]. Oxytetracycline biosynthesis. J Biol Chem. 2010 Sep 3;285(36):27509-15.

[3]. A New Treatment Method for Herpes Simplex Virus Type 1-related Skin Lesions. Scientific & Academic. 2019; 8(1): 6-8.

Oxytetracycline (internal use) can cause developmental toxicity according to state or federal government labeling requirements.
Oxytetracycline is a tetracycline used for treatment of infections caused by a variety of Gram positive and Gram negative microorganisms including Mycoplasma pneumoniae, Pasteurella pestis, Escherichia coli, Haemophilus influenzae (respiratory infections), and Diplococcus pneumoniae. It has a role as an antibacterial drug, a protein synthesis inhibitor, an antimicrobial agent, an anti-inflammatory drug and a bacterial metabolite. It is a tautomer of an oxytetracycline zwitterion.
A tetracycline analog isolated from the actinomycete streptomyces rimosus and used in a wide variety of clinical conditions.
Oxytetracycline anhydrous is a Tetracycline-class Antimicrobial.
Terramycin has been reported in Streptomyces anthocyanicus, Streptomyces varsoviensis, and other organisms with data available.
A TETRACYCLINE analog isolated from the actinomycete STREPTOMYCES rimosus and used in a wide variety of clinical conditions.

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Drug Indication
Oxytetracycline is indicated for treatment of infections caused by a variety of Gram positive and Gram negative microorganisms including Mycoplasma pneumoniae, Pasteurella pestis, Escherichia coli, Haemophilus influenzae (respiratory infections), and Diplococcus pneumoniae.

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Mechanism of Action
Oxytetracycline inhibits cell growth by inhibiting translation. It binds to the 30S ribosomal subunit and prevents the amino-acyl tRNA from binding to the A site of the ribosome. The binding is reversible in nature. Oxytetracycline is lipophilic and can easily pass through the cell membrane or passively diffuses through porin channels in the bacterial membrane.
Tetracyclines inhibit bacterial protein synthesis by binding to the 30 S bacterial ribosome and preventing access of aminoacyl tRNA to the acceptor (A) site on the mRNA-ribosome complex. They enter gram-negative bacteria by passive diffusion through the hydrophilic channels formed by the porin proteins of the outer cell membrane, and active transport by an energy-dependent system that pumps all tetracyclines across cytoplasmic membrane. Although permeation of these drugs into gram-positive bacteria is less well understood, it also is energy requiring. At high concn, these cmpd impair protein synthesis in mammalian cells. However, because mammalian cells lack the active transport system found in bacteria, and the ribosomal target is less sensitive, tetracyclines are selectively active against bacteria. /Tetracyclines/
The tetracycline antibiotics ... can produce neuromuscular blockade, possibly by chelation of Ca+2. /Tetracyclines/

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Therapeutic Uses
Mesh Heading: anti-bacterial agents
Antibiotics, Tetracycline
... Possess wide range of antimicrobial activity against gram-positive and gram-negative bacteria ... some microorganisms innately insensitive to many chemotherapeutic agents, such as rickettsiae, mycoplasma, chlamydia agents of lymphogranuloma venerum, psittacosis, inclusion conjunctivitis, and trachoma and amebae. /Tetracyclines/
The tetracyclines are active against a wide range of aerobic and anaerobic gram-positive and gram-negative bacteria. They also are effective against some microorganisms that are resistant to cell-wall-active antimicrobial agents, such as Rickettsiae, Coxiella burnetii, Mycoplasma pneumoniae, Chlamydia spp, Legionella spp, Ureaplasma, some atypical mycobacteria, and Plasmodium spp. They are not active against fungi. /Tetracyclines/
For more Therapeutic Uses (Complete) data for OXYTETRACYCLINE (28 total), please visit the HSDB record page.

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Drug Warnings
GENERIC INEQUIVALENCE HAS BEEN DEMONSTRATED FOR SOME OXYTETRACYCLINE FORMULATIONS, ALTHOUGH INDIVIDUAL VARIATION PREVENTED SIGNIFICANT DIFFERENCES BEING SHOWN IN ALL BUT MOST EXTREME CASES.
FOOD, MILK, NONSYSTEMIC ANTACIDS & IRON PREPN INTERFERE WITH ORAL ABSORPTION.
... Not active against any true viruses, yeasts, or fungi. /Tetracyclines/
Topical admin is best avoided because of high risk of sensitization, except for use in eye ... Should never be injected intrathecally. /Tetracyclines/
For more Drug Warnings (Complete) data for OXYTETRACYCLINE (38 total), please visit the HSDB record page.

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Pharmacodynamics
Oxytetracycline is known as a broad-spectrum antibiotic due to its activity against such a wide range of infections. It was the second of the tetracyclines to be discovered. Oxytetracycline, like other tetracyclines, is used to treat many infections common and rare. Its better absorption profile makes it preferable to tetracycline for moderately severe acne, but alternatives sould be sought if no improvement occurs by 3 months.

C22H22CAN2O9

498.095

7179-50-2

Oxytetracycline;79-57-2;Oxytetracycline hydrochloride;2058-46-0;Oxytetracycline dihydrate;6153-64-6

54675779

Light-yellow crystals or needles from aqueous MeOH
Pale yellow to tan, crystalline powder

0.06

7

10

2

33

1000

6

[Ca+2].NC(C1C(=O)[C@@H](N(C)C)C2[C@H]([C@@H]3[C@@](O)(C)C4=CC=CC([O-])=C4C([O-])=C3C(=O)[C@]2(O)C=1O)O)=O

OWFJMIVZYSDULZ-PXOLEDIWSA-N

InChI=1S/C22H24N2O9/c1-21(32)7-5-4-6-8(25)9(7)15(26)10-12(21)17(28)13-14(24(2)3)16(27)11(20(23)31)19(30)22(13,33)18(10)29/h4-6,12-14,17,25-26,28,30,32-33H,1-3H3,(H2,23,31)/t12-,13-,14+,17+,21-,22+/m1/s1

(4S,4aR,5S,5aR,6S,12aR)-4-(dimethylamino)-1,5,6,10,11,12a-hexahydroxy-6-methyl-3,12-dioxo-4,4a,5,5a-tetrahydrotetracene-2-carboxamide

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)